From the evening of 10/24/26 until the morning of 12/7/26 - hikers may not enter the Elk Lake Conservation Easement.
All hiking is closed during this time.
Read on DEC's siteEverything DEC is currently warning Adirondack hikers about, newest first, in DEC's own words.
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Not affiliated with NYS DEC. Conditions change — verify with DEC before you go. Emergencies: 911 or 1-833-NYS-RANGERS.
206 current alerts · 6 new this week
All hiking is closed during this time.
Read on DEC's siteThe trail has not been maintained since Tropical Storm Irene in 2011.
Trails: Cold Brook Trail
Read on DEC's siteThe portion of the trail crossing private land has been closed to public use by the landowner. Trespassing on those lands is now prohibited. The summit of Little Porter Mountain can still be accessed from the Marcy Field Trailhead or the Cascade Mountain Trailhead.
Read on DEC's siteFor more detail, refer to the map on the Grass River Complex webpage.
Read on DEC's siteFor more details refer to the map on the Raquette Boreal Complex webpage.
Read on DEC's siteThe washout is 0.25 miles south of the parking area at Debar Meadows. Skiff Pond can be accessed by taking the Debar Meadows to Meacham Lake Trail for about 1.8 miles to the intersection with the Skiff Pond Trail and turning east towards Skiff Pond.
Trails: Skiff Pond Trail
Read on DEC's siteCampsite 8 along Otterbrook Road in Horseshoe Lake Wild Forest will be closed starting Monday, June 1, 2026 for accessible improvements to the site.
Read on DEC's siteTrails: Shallow Lake Trail
Read on DEC's siteThe Spruce Mountain Fire Tower Trail is the only recreation currently available on this tract and is closed to the public during regular bug game hunting season in the northern zone, which includes bear and deer seasons. Public ATV access is NOT permitted on any conservation easement lands in this area (Northway Properties and Lyme Adirondack Forest Company). State police and NYS Rangers will be called for trespass violations.
Read on DEC's siteThe trail crosses private lands and the landowner revoked permission for the public to cross. Hikers must use the formal Kane Mountain Trailhead off Green Lake Road.
Read on DEC's siteTrails: Spruce Mountain Trail
Read on DEC's sitePrior to DEC's construction of the 2 designated campsites on Boreas Ponds, primitive camping must be done at least 150' from the shoreline. Signage is installed at impacted sites within 150' of the shoreline to remind campers not to use these areas and to camp at an appropriate distance. Thank you for helping to protect the natural resource and the Wilderness Experience of all future users by following the 150' rule when selecting a site.
Read on DEC's siteThis bridge serves the Lean-to and Campsites and is access off the southern end of the Lake Arnold Trail. Please use caution if utilizing the bridge. DEC is starting the planning process to replace the bridge and will share updates as they are available.
Read on DEC's siteThe Calamity Brook Trail, starting at the Upper Works, is the main access to Flowed Lands, Lake Colden and hikes radiating from that basin. During extensive rain events or high water this trail may not be passable. Alternative routes will also have high water crossing challenges, including the two crossings of the Opalescent River on the East River Trail and the crossing of the Opalescent River on the Lake Arnold Trail before the junction with the Feldspar Trail. The Cold Brook Pass Trail between the Indian Pass Trail and Lake Colden has not been maintained by DEC in over a decade and is not a viable option for these conditions given water crossings on the Indian Pass Trail. DEC will be repairing the bridge in late fall 2026.
Trails: Calamity Brook Trail
Read on DEC's siteIn the area of the Opalescent River crossing there is extensive flooding. There are several social trails in this area to try and avoid the deepest parts. Old sections of bog bridging are floating and not reliable. DEC is working on a plan to fix this in the coming years.
Trails: Lake Arnold Trail
Read on DEC's siteThese 2 sites were located south of Avalanche Lake, between the lake and Caribou Jct. The closure was related to the 2025 Landslides on Mt. Colden. DEC is in the planning process to relocate these campsites.
Read on DEC's siteDEC will be replacing this register box sometime in late 2026. Please plan ahead and prepare for backcountry trips in this area.
Read on DEC's siteThe first bridge coming from the Raquette Falls trail (~.5 miles from junction) is broken and unsafe for Horse use. This bridge will be removed in 2025 to allow for safer passage by horses and a plan developed for replacement. The 2nd bridge (~1.0 mile from junction) has been washed downstream but ability to ford this crossing is with horses and rock hop for hikers is clear.
Read on DEC's siteThe Mr. Van Ski Trail between the Van Hoevenberg Trail (to Mt. Marcy) and the South Meadow Trail is currently flooded with beaver activity and several bridges missing. Hikers should avoid using this segment of the trail as it is impossible to traverse without wading through various water levels. Hikers choosing to access the Klondike Trail or the Mr. Van Lean-to can access this from the South Meadows Trailhead and South Meadow Trail.
Read on DEC's siteHikers must park at the Upper Elk Lake Road parking lot on the west side of the Elk Lake Road approximately 2.3 miles south of the Elk Lake Trailhead. Please respect the parking rules to help ensure this access is maintained and there are no impacts to fire and rescue access.
Read on DEC's siteViolators will be towed.
Read on DEC's siteThese crossings require some planning when there is rain in the forecast or there is high water. Several of these crossings can rise significantly during a rainstorm, being easily crossed in the morning and by afternoon more challenging.
Read on DEC's siteKnown trails impacted by high water The Round Pond Trail to Dix, crossing of the North Fork of the Boquet RiverThe Phelps Trail, crossing of Johns Brook above Bushnell FallsThe Mr. Van Ski Trail crossing of South Meadow BrookThe Van-Hovenberg Trail to Marcy Crossing of Phelps Brook above Marcy Dam and at Indian FallsThe Lake Arnold Trail crossing of the Opalescent River (floating bog bridges)The Herd Paths to Street and Nye Mtns, crossing Indian Pass BrookThe Indian Pass Trail (north and south) crossings of Indian Pass BrooksThe Calamity Brook Trail crossing at the High-Water Bridge, over Calamity Brook The East River Trail crossing the Opalescent River before Allen Mtn Trail Junction and also outlet of Flowed LandsThe Northville Placid Trail crossing of Seward Brook near the Ouluska Lean-toThe Cold River Crossing at Duck Hole to head south on the Bradley Pond Trail.
Trails: Phelps Trail, Phelps Trail, Round Pond Trail
Read on DEC's siteThese areas are challenging to navigate. Please use caution and turn back if it is too difficult for your party to safely cross.
Trails: Pitchoff Mountain Trail
Read on DEC's siteJust past the Trail Register, the trail has been eroded away and there are exposed roots and rounded rocks. Hikers should avoid traveling on adjacent private property and stay in the trail corridor, using caution to traverse this area.
Read on DEC's siteDEC is working on a plan to source materials and repair the roof. The damage does not impact users safety, though you might get wet if it is raining!
Read on DEC's siteAs of Tuesday, September 15, the 24.6-mile section of the St. Lawrence County Multi-Use Trail that crosses the Tooley Pond, Grass River, and Long Pond Conservation Easements is closed for the season.
Read on DEC's siteKeep a safe distance, use caution, and always yield to them.
Read on DEC's siteKeep a safe distance, use caution, and always yield to them.
Read on DEC's siteIn 2025, five new primitive tent sites were opened and five existing sites were permanently closed. A map and more info can be found on Saranac Lakes Wild Forest.
Read on DEC's siteSections of these trails are very muddy. Hikers and bikers should avoid using the Purple Trail or the trail up the east side of Cobble Hill.
Read on DEC's siteKeep a safe distance, use caution, and always yield to them.
Read on DEC's siteLiberty Road and Wolf Pond Mountain Road are closed to ALL public motorized and non-motorized access from September 27 through the close of the Northern Zone big game rifle season, December 6, 2026. These roads will reopen to public access on December 7, 2026.
Read on DEC's sitePiney Ridge Road is closed to ALL use until further notice due to severe storm damage.The Cold Brook Public Use Area can be accessed via the Cold Brook parking area on Standish Road. The parking area is located 1.8 miles south of the Piney Ridge Road gate on the Standish Road.
Read on DEC's siteKeep a safe distance, use caution, and always yield to them.
Read on DEC's siteThe road will remain closed at this point until repairs are made.
Read on DEC's siteUsers should exercise caution and be aware of changing road conditions throughout the seasons. (12/2025)
Read on DEC's site(12/2025)
Read on DEC's siteRed Horse Trail: Hikers will need to navigate around two bridges that have washed away between Witchopple and Clear Lakes, and beaver flooding between Salmon and Witchopple Lakes.
Trails: Red Horse Trail
Read on DEC's siteUsers should expect wet conditions and may require short bushwacks around flooded sections of trail until water levels recede. Users of the Cranberry Lake 50 Trail should note that hiking along Six Mile Creek Trail and bypassing the Olmstead Pond Loop provides enough mileage to qualify for the badge.
Read on DEC's siteSections of the trail are flooded and beaver dams have been built on parts of the trail. Sections of the trail may be impassable.
Read on DEC's siteRepairs are expected to be completed by October 12, 2026. Please do not tamper with staged construction materials or lean-to pieces.
Read on DEC's siteParking at the NPT Lake Durant / Tirrell Pond trailhead on NY Routes 30 and 28 will be limited due to a Department of Transportation bridge construction project.
Read on DEC's sitePickwickett Pond Road is closed but the public may carry into the Fishing Brook canoe launch.
Read on DEC's siteIf the gate is open, it is only because contractors are working in the area. Follow all signs and do not attempt to drive up this road.
Read on DEC's siteThere will be no motor vehicle access to the Brooktrout Lake Trailhead and Falls Pond Outlet. Pedestrians may cross the stream to access points beyond the road closure.
Read on DEC's siteDue to an unforeseen bridge failure at Payne Brook, the gate at Cedar River Headquarters will remain closed. The road is currently closed between Wilson Ridge Trailhead and Cedar River Headquarters gate.
Read on DEC's siteA temporary foot bridge is in place.
Read on DEC's siteThe trail east of Otter Brook is overgrown and blown down trees may impede travel.
Trails: Otter Brook Trail
Read on DEC's siteThe Northville-Placid Trail has been rerouted around an area of significant beaver flooding in the West Canada Lakes Wilderness area between West Lake and Mud Lake. Please follow all signs and trail markers.
Trails: Northville-Placid Trail, Northville-Placid Trail, Northville-Placid Trail, Northville-Placid Trail
Read on DEC's siteRepairs are expected to be completed by October 12, 2026. Please do not tamper with staged construction materials or lean-to pieces.
Read on DEC's siteThe Sucker Brook Trail which connects the Northville-Placid Trail and the DEC Lewey Lake Campground is unmaintained beyond the height of ground between Lewey Mountain and Cellar Mountain, about 4.4 miles west of the campground.Beyond the height of ground blowdown, wet stretches of trail, and beaver activity make the trail difficult to follow.Access to Colvin Brook Lean-to and the Northville Placid Trail may be gained from the Moose River Plains trailhead off Limekiln Lake - Cedar River Road.
Trails: Northville-Placid Trail, Northville-Placid Trail, Northville-Placid Trail, Northville-Placid Trail, Sucker Brook Trail
Read on DEC's siteBeaver activity has contributed to wet and muddy trail conditions on the following trail sections:North of the Carry lean-to in West Canada Lake WildernessSouth Pond to West Lake in West Canada Lake Wilderness
Read on DEC's siteWet trail conditions are present where the trail crosses the edge of a beaver vly 2.4 miles in from the wilderness boundary at Indian Lake. Fallen trees and encroaching vegetation may impede travel on the interior trail segments closer to Horn Lake.
Trails: Horn Lake Trail
Read on DEC's siteHikers should be prepared to encounter segments of flooded and muddy trail conditions after periods of significant rain.
Read on DEC's siteTrails: Cedar Lakes Trail
Read on DEC's siteThe Sucker Brook Trail which connects the Northville-Placid Trail and the DEC Lewey Lake Campground is unmaintained beyond the height of ground between Lewey Mountain and Cellar Mountain, about 4.4 miles west of the campground.Beyond the height of ground blowdown, wet stretches of trail, and beaver activity make the trail difficult to follow.Access to Colvin Brook Lean-to and the Northville Placid Trail may be gained from the Moose River Plains trailhead off Limekiln Lake - Cedar River Road.
Trails: Northville-Placid Trail, Northville-Placid Trail, Northville-Placid Trail, Northville-Placid Trail, Sucker Brook Trail
Read on DEC's sitePlease make plans to cross the stream at low and normal water levels via rock hopping and shallow fording.
Trails: Big Pond Trail
Read on DEC's siteFor questions or concerns please contact the Northville DEC office at: 518-863-4545.
Read on DEC's siteRoads will remain passable but occasional delays are expected.
Read on DEC's siteImprovements on this trail system are being completed this season. Please stay on the designated trail and take care with your footing in areas where work is occurring.
Read on DEC's siteThe public no longer has access to the Chimney Mountain Trail, Puffer Pond Trail, and Kings Flow East Trail from this location. This is private land. There is no easement for public access. Hikers can use the DECinfo Locator online map to explore alternative trails.
Read on DEC's siteTrails: East Branch Trail, East Branch Trail
Read on DEC's siteIf you are planning a trip near these dates, please call or email ahead to confirm that the gate is open - (518) 623-1240 or [email protected]. There are no public trails to this cave. This is now a bushwhack. Please plan accordingly and respect private property. At all other times of the year the gate will be closed to protect the bat population.
Read on DEC's siteNever approach or feed any wildlife, report unusual animal behavior at 518-623-1200. In an emergency, call 911 or NYSDEC Dispatch at (518) 897-1326.
Read on DEC's siteThe entire site is closed (no camping or campfires) until further notice.
Read on DEC's siteThe boardwalk beyond the bridge is still out. People should expect wet conditions, and up to knee deep water until it can be replaced.
Trails: Pharaoh Lake Trail
Read on DEC's siteTrails: Stone Dam Trail
Read on DEC's siteTrails will be cleared as manpower allows.
Read on DEC's siteTrails: Bear Lake Trail
Read on DEC's siteThe stream may not be passable in times of high water.
Read on DEC's siteHaskell/West Creek Road is a rough road, and 4-wheel drive trucks, SUVs and other high clearance vehicles are recommended.Travel beyond Seabury Brook is challenging as road conditions are poor.The road is closed beyond the Honnendaga Outlet Bridge because the bridge is in disrepair. Landowners of the private lands beyond may choose to use the bridge to access their lands.
Read on DEC's siteTrails: Big Otter Lake Trail, Big Otter Lake Trail, Lost Creek Trail, Middle Branch Lake Trail
Read on DEC's siteTrails: Lost Lake Trail
Read on DEC's siteTrails: Lost Lake Trail
Read on DEC's siteBeyond Tommy Roaring Brook, the road is impacted by beaver activity and requires crossing on dam for access around flooded sections of trail. Users should exercise caution when crossing dam and wading through water may be necessary.
Read on DEC's siteCrossing at this location may be hazardous.
Trails: Aspen Trail
Read on DEC's siteHorses may ford Otter Creek at the old bridge site. Snowmobiles can cross Otter Creek at the Eatonville Falls Bridge.
Read on DEC's siteAll users should be prepared to access the area by alternate means. For example, through portaging over the beaver dam by the boat landing and paddling further up Andy's Creek, one can then access the trail and the lean-to.
Read on DEC's siteAn old beaver den can be used to cross the outlet.
Read on DEC's siteBe alert of trail reroutes.
Trails: Cascade Lake Trail
Read on DEC's siteThe Fire Tower on Hadley Mountain is a nearby alternative.
Read on DEC's siteCaution is advised when hiking the trail.
Read on DEC's siteWaters Mill Pond Trail: The bridge that goes over North Creek heading towards Waters Mill Pond has been removed and plans to replace it will take place this winter and into the next year. Anyone looking to access Waters Mill Pond from the west will need to ford the creek.
Read on DEC's siteThere are still soft spots and areas of washout. Please use caution.
Read on DEC's siteTrails: Mud Pond Trail
Read on DEC's siteTrails: Pine Orchard Trail
Read on DEC's siteThe Fire Tower on Hadley Mountain is a nearby alternative.
Read on DEC's siteWhen water is high, this spot is difficult to cross.
Trails: Cotter Brook Trail
Read on DEC's siteTrails: East Stony Creek Trail
Read on DEC's siteFrom May 1 through October 31, reservations are required to access the parking lot, trailheads, and trails located on the privately owned 7,000-acre AMR property in the town of Keene in the Adirondack High Peaks region. For a list of frequently asked questions, visit AMR's website. NOTE: This program is managed directly and exclusively by AMR, not DEC. For questions or concerns about the reservation system, please directly contact AMR using the Contact Us section of their website.
Read on DEC's siteNYSDEC requires the use of bear-resistant canisters by overnight users in the Eastern High Peaks Wilderness between April 1 and November 30. NYSDEC encourages campers to use bear-resistant canisters throughout the Adirondack backcountry. Bear canisters should be used to store all food, food garbage, toiletries, and other items with a scent. Canisters should be stored a minimum of 100ft from tents, lean-tos and cooking sites and kept closed whenever they are not being accessed. Learn more about bear canisters and avoiding human-bear conflicts.
Read on DEC's siteThe Adirondack Canoe Route is part of the 740-mile Northern Forest Canoe Trail (NFCT) which links the waterways of New York, Vermont, Québec, New Hampshire and Maine.
Read on DEC's siteThere is a temporary cover for this hole. DEC has started the planning process to repair/replace this lean-to.
Read on DEC's siteThe Hidden Cove Lean-to on the eastern shore of Long Lake, in the Adirondack Canoe Route Zone of the High Peaks Wilderness, will be worked on throughout the fall of 2026 starting the weekend of 10/17. Please do not disturb staged building materials. A notice will be posted if the lean-to is unavailable.
Read on DEC's siteDo not trespass on AMR lands and waters or participate in any unauthorized activities.
Read on DEC's sitePlease call for current year's code at 518-623-1200.
Read on DEC's siteThe amendments describe the management, access, and public recreational opportunities available for the lands and waters on this tract of land.
Read on DEC's sitePlease respect areas marked with cones and flagging so that the crews and equipment can accomplish this task.
Read on DEC's siteEach year there are multiple rescues and injuries that result from hikers underestimating the climb. If you venture, know your limits beforehand, do not rely on any ropes or webbing that are left in the Trap Dike, and it is strongly recommended that you wear a helmet.
Read on DEC's siteThe Moose Pond Horse Trail, which leaves the Newcomb Lake Road north of the Camp Santanoni Farm Complex provides access into the High Peaks Wilderness, the areas west of the Santanoni Mountain Range and connects with the Cold River Horse Trail Network.
Trails: Moose Pond Horse Trail
Read on DEC's siteThose climbing these peaks should navigate with a map and compass rather than follow the paths created by others.
Read on DEC's siteParking at the trailhead and hiking the trail are prohibited on weekends.
Read on DEC's siteThe lands of the Dix Mountain Tract are now part of the High Peaks Wilderness.All regulations applicable to the High Peaks Wilderness are now in effect including, but not limited to:Group size: Groups should consist of no more than 15 hikers and no more than 8 campers.Glass Containers: Glass containers are prohibited.Information about the former Dix Mountain Area may be found in the High Peaks Wilderness section above.
Read on DEC's siteThe road is not maintained from October - April, effectively closing it to public automobile use during that time.
Read on DEC's siteThe brook is passable during low water conditions.
Read on DEC's sitePlease respect posted signage and barricades in work areas and email [email protected] with questions.
Read on DEC's siteDue to areas of erosion, it is recommended that only high clearance vehicles be used on Madawaska Pond Road.
Read on DEC's siteThe bridge over Ray Brook has been replaced.
Trails: Scarface Mountain Trail
Read on DEC's siteSnowmobile access is limited to designated routes only and as conditions permit. Cars, trucks, ATV's and UTV's are not allowed. Park at designated parking areas and access by non-motorized means only.
Read on DEC's siteRiders must stay on the designated C8 Route along Fern Lake Road, there is no alternate route through the property.
Read on DEC's siteMoose Pond Club Road is open, allowing public access to several primitive campsites, and the parking lot at the trailhead for the Vanderwhacker Mountain Fire Tower Trail.
Read on DEC's sitePlease call for current year's code.
Read on DEC's siteThe railroad is undergoing maintenance adjacent to the Five Ponds Wilderness Area and William C. Whitney Wilderness Area. There is an increase in traffic from trains and equipment working on rehabilitation of the railroad through this section. Users are reminded that the railroad tracks between Harrington Brook and the carry to Clear Pond and Bog Lake (Five Ponds Wilderness) are not a DEC trail and should not be used as a canoe carry when the railroad is active.
Read on DEC's siteThe washouts are located about 0.75 miles and 1.0 miles from the trailhead.
Read on DEC's siteThe railroad is undergoing maintenance adjacent to the Five Ponds Wilderness Area and William C. Whitney Wilderness Area. There is an increase in traffic from trains and equipment working on rehabilitation of the railroad through this section. Users are reminded that the railroad tracks between Harrington Brook and the carry to Clear Pond and Bog Lake (Five Ponds Wilderness) are not a DEC trail and should not be used as a canoe carry when the railroad is active.
Read on DEC's siteHigh clearance vehicles are recommended to access Barker Pond.
Read on DEC's siteThe use of the road by people other than authorized personnel with administrative duties is prohibited and is considered trespassing.
Read on DEC's siteRock Dam Road is open.
Read on DEC's siteThe trail may be difficult to follow in areas, especially closer to Sly Pond.
Trails: Sly Pond Trail
Read on DEC's siteAccess to many popular destinations in the West Canada Lakes Wilderness from the Jessup River Road (Perkins Clearing) and Limekiln Lake-Cedar River Road (Moose River Plains Complex) is limited in off season months due to seasonal road closures. Motor vehicle access to the Spruce Lake Trailhead, Pillsbury Mountain/French Louie Trailhead, Brooktrout Lake Trailhead and others is prohibited.
Read on DEC's siteBe prepared to adapt or have a backup plan.
Read on DEC's sitePlease call for current year's code.
Read on DEC's siteTrails: Big Pond Trail
Read on DEC's sitePlease check the DECinfo Locator page for up-to-date maps reflecting this addition.
Trails: Jones Hill Trail
Read on DEC's siteNon-motorized recreation on the Crotched Pond tract is allowed outside of the 1-acre camp envelopes.
Read on DEC's siteMoose Pond Club Road is open, allowing public access to several primitive campsites, and the parking lot at the trailhead for the Vanderwhacker Mountain Fire Tower Trail.
Read on DEC's sitePlease call for current year's code.
Read on DEC's siteIntersections provide directional signage that reflect the marker color changes. Please be mindful and prepared to adapt.
Read on DEC's siteThere are many herd paths, old roads and skid trails throughout the unit, those bushwacking should navigate with a map and compass rather than follow the paths created by others. Unofficial trails do not receive maintenance from DEC staff.
Read on DEC's siteBlow down will be cleared as manpower allows.
Read on DEC's siteThere is an active railroad present in the summer. Camping is prohibited in and around the hand launch site during June, July and August.
Read on DEC's siteATVs use is prohibited.
Read on DEC's siteVegetation has begun to grow in on the six sites making them harder to find.
Read on DEC's siteHowever, travel beyond Mill Creek Lake will be limited by poor road conditions and snowmobile bridges not designed to support vehicles.
Read on DEC's siteTrails: West Mountain Trail
Read on DEC's siteUsers should travel this route carefully and at low speed.
Read on DEC's siteCamping is available only at the four designated locations.
Read on DEC's siteState police and NYS Rangers will be called for trespass violations.
Read on DEC's siteState police and NYS Rangers will be called for trespass violations.
Read on DEC's siteTrails: Northville-Placid Trail
Read on DEC's siteTrails: Northville-Placid Trail
Read on DEC's siteSeveral cars have become stuck. Only high clearance 4-wheel drive vehicles should use the road.
Read on DEC's siteIn wet times of year, hikers will have to go through some water to enter and exit the bridge.
Trails: Oregon Trail
Read on DEC's siteCheck the fire rating map for daily updates
Read on DEC's siteExpect water levels to rise with new rainfall. Check the USGS Current Water Data for New York for stream flow of selected waters. (Personal Flotation Devices (PFDs aka lifejackets) are required from November through May.)
Read on DEC's siteThese are forecast temperatures for base elevations throughout the region. Weekend temperatures in the region at BASE elevations are expected to have highs in the low-50s (Friday) and lows in the low-20s. Check the National Weather Service's Mountain Point Forecast for more accurate forecasts at elevation on or near your intended route.
Read on DEC's siteIt's still fall but snow is falling! The High Peaks have already seen dustings of snow, and this weekend we expect to see some more of that white stuff even at lower elevations.
Read on DEC's siteThe sunset is before 7 PM! Forgetting a headlamp is one of the most common causes of search-and-rescues. Remember- 2 is 1, and 1 is none.
Read on DEC's siteLayer properly to stay warm with moisture-wicking (non-cotton) inner layers, insulating mid-layers, and water/wind-resistant outer layers. Anticipate losing 5 degrees Fahrenheit for every 1,000 feet of elevation gain!
Read on DEC's site