Lost Lake Trail

A small lake coverd in lily pads surrounded by a forest.

This 2.8-mile moderate loop earns its name: Lost Lake delivers scenic water views, waterfowl, and if you're lucky, beaver dams and wildflowers. The elevation gain (300 feet) is steady but not crushing—expect 1-2 hours if you move at purpose. The real hazard: this area has serious bear and bison traffic. Keep your head on a swivel and your bear spray loaded."

Quick facts

Distance Miles: 2.8
Route Type: Loop (or out-and-back segments possible)
Difficulty Level: Moderate
Elevation Gain Feet: 300

Trail profile

Distance Miles: 2.8
Route Type: Loop (or out-and-back segments possible)
Difficulty Level: Moderate
Elevation Gain Feet: 300
Estimated Time: 1-2 hours if you maintain steady pace; 2-3 hours with wildlife stops and photo breaks
Trail Surface: Dirt and gravel with firm bench sections. Roots in forested areas, loose scree on hillside contours. Well-packed from heavy use.
Trail Features: Lost Lake with mountain backdrop
Waterfowl (ducks, geese) at lake margins
Wildflower meadows (lupine, balsamroot)
Sagebrush hilltops with ridge views
Possible beaver dams and evidence
Petrified Tree historic site
Roosevelt Lodge architectural landmark
Trail Highlights: Lost Lake reflections with mountain frame, waterfowl and possible beaver sightings, wildflower displays in early summer, open sagebrush vistas, Petrified Tree curiosity stop, high probability of black bear and bison encounters (not optional).

Trailhead & access

Trailhead Location: Roosevelt Lodge (primary; behind the lodge) or Petrified Tree parking area west of Tower Junction
Parking Lot Size: Roosevelt Lodge main lot: unknown capacity. Petrified Tree overflow lot: unknown capacity.
Parking Fill Time: Roosevelt Lodge lot fills by 7-8 AM on peak days (Jul-Aug); Petrified Tree lot fills by 8-9 AM. Shoulder seasons rarely fill before noon.
Shuttle Required: 0
Shuttle Details: Not required. Two trailhead options (Roosevelt Lodge and Petrified Tree parking) allow flexibility. Starting at Petrified Tree avoids Roosevelt congestion and adds directional variety to the loop.

Permits & conditions

Permit Details: No permits required for day hiking on this trail. Register at the trailhead if requested by rangers.
Fees: $35 park entrance fee (7-day pass; valid for all private vehicles). Lost Lake Trail itself is free once park access is paid.
Trail Status: Open
Seasonal Closures: Rarely closed. Snow and ice may temporarily restrict access or require winter gear (Nov-Apr), but the trail is typically walkable year-round. Check park conditions before winter attempts—snowpack varies by elevation and aspect.

Facilities & rules

Restrooms At Trailhead: 1
Water Sources: No reliable potable water sources on the trail. A small creek near Lost Lake may flow in summer, but water quality is not guaranteed—filter aggressively if you draw from it. Carry all water needed (2+ liters minimum). Never drink untreated water in bear country (cryptosporidium risk and wildlife pollution).
Accessibility: Rooty and steep in forested sections; firm bench sections on ridge. Not suitable for mobility devices, crutches, or strollers. The elevation gain and uneven terrain require solid leg strength and balance. Not wheelchair accessible.

Safety & strategy

Hazards: Black bears (frequent encounters—high likelihood)
American bison (aggressive if approached)
Horseback riders (trail conflict points)
Steep bench drop-offs (exposure risk)
Full-sun exposure on sagebrush sections (heat/dehydration)
Terrain roots and uneven ground (ankle twist risk)
Weather exposure on ridge crests (wind, sudden storms)
Hazard Details: This area is home to many bears and bison—the NPS safety notes specifically warn of frequent encounters. Use caution, make noise, and keep 100+ yards from wildlife. Trail shared with horseback riders; move to the downhill side and stand still until they pass. Bench section has steeper drop-offs; not technically exposed, but a slip matters. Sagebrush sections lack shade; sun exposure and dehydration are real risks in summer heat. Roots in forested areas can catch toes. Ridge sections catch wind and sudden weather.
Cell Service: Spotty to nonexistent. Do not rely on cell signal for emergencies. Inform someone of your planned route and expected return time before departure. In emergencies, make noise to alert nearby hikers or rangers, or hike out and report to Tower Ranger Station.
Crowd Level: Moderate to heavy during peak season (Jul-Aug), especially weekends and midday. Much quieter during shoulder seasons (May, Jun, Sep, Oct) and off-season (Nov-Apr). Popular enough that solitude is rare in summer.
Peak Crowd Times: July-August (peak summer), especially 10 AM-4 PM. Weekends busier than weekdays. Early morning (before 8 AM) and late afternoon (after 4 PM) offer some breathing room even in summer.
Best Season: May through September. Roads typically open mid-April; September marks the onset of frost and shortened daylight. Winter hiking is possible but requires winter-specific gear (crampons, microspikes, extra water/insulation).
Best Time To Visit: May through September for optimal weather and full access. Start by 6 AM to beat crowds and catch bears/bison in dawn activity—they're most active before 9 AM and after 5 PM. Midday sun in July-August is brutal on sagebrush sections; shoulder seasons (May-Jun, Sep-Oct) offer cooler temps and better wildlife viewing odds.
Tips Advice: Carry 2+ liters of water minimum—sagebrush terrain has zero reliable sources.
Bear spray is not optional—holster it on your hip belt, not in a pack.
Make constant noise (talk, use a bear bell, clap)—surprise encounters are dangerous.
Bring trekking poles for the descent; 300 feet down hammers the knees.
Sunscreen and a wide-brimmed hat are mandatory on the bench section (exposed ridge).
Hike with a partner minimum; solo hiking here is reckless given bear density.
Check trail conditions before winter trips—icy sections need crampons.
Never stop at the first lake viewpoint; continue to the far side for the real reflection shot.

More details

Park Area: Northern Yellowstone near Tower Junction
Trail Markers: Well-marked and heavily used. The main trail is obvious, but junctions near Petrified Tree parking and Tower Ranger Station require attention to stay on the loop. Cairns and worn tread make the route clear. A map is wise to confirm orientation at intersections.
Dogs Allowed: No. Pets are not permitted on Yellowstone hiking trails per NPS regulation.
Biking Allowed: No. This is a hiking trail only. Mountain bikes are not permitted. Horses are allowed (trail is shared with horseback riders)—give them the downhill side of the trail and stand still until they pass.
Shade Level: Partial sun and shade. Forested sections near Roosevelt Lodge offer canopy; the bench climb and sagebrush terrain are fully exposed to direct sun. UV exposure is significant on ridge sections. Sunscreen and a wide-brimmed hat are non-negotiable.
Emergency Contacts: Tower Ranger Station (nearest official contact, park-managed). Yellowstone emergency: dial 911 if service is available; otherwise hike out to the nearest ranger station or populated area. In bear encounters, follow NPS guidance: make yourself large, back away, use bear spray as last resort.
Map Recommended: 1
Snow Dates: Winter snow possible November through April. Trail remains accessible, but snow depth and icy conditions vary by year and elevation. Expect packed snow in midwinter; crampons or microspikes are necessary. Spring (April-May) sees snowmelt and mud in low-lying sections.
Mud Season: April-May (spring snowmelt creates slush and muddy low-lying sections near creeks). July can see brief wet spells after heavy thunderstorms. Check trail reports before visiting during these windows.
Wildflower Peak: Late June through July. Lupine, balsamroot, geranium, and other forbs blanket the sagebrush hillsides. Peak bloom is typically early-to-mid July in Yellowstone's high elevation.
Fall Colors Peak: Late September through early October. Aspen groves near Roosevelt and Tower show subtle golds and yellows. Not dramatic, but the crisp air and thin crowds make it rewarding.
Bug Season: July-August peak mosquito season. Bring insect repellent (DEET or picaridin). Consider long sleeves and pants in dawn/dusk hours (peak feeding times). July is typically worse than August in Yellowstone.
Insider Tips: Start at 6 AM or earlier to beat crowds and catch bears in peak activity (dawn foraging).
The first lake viewpoint (Mile 1.5) will tempt early turnarounds—resist it. Continue to the far side of Lost Lake (beyond Mile 2) for the real reflection shot with mountain backdrop and calm water (beaver work).
Bring trekking poles—the descent from the bench hammers knees; poles cut stress by 40%.
Horseback riders often use this trail weekday mornings (tourist rides from Roosevelt)—hike early or go mid-afternoon to avoid horse encounters.
Water caching: Ranger office (Tower Ranger Station) can advise if Lost Lake Creek is reliable for filtering; don't assume.
Golden hour (first 2 hours or last 2 hours of daylight) provides best light for camera work and water reflections.
The bench section is the real sweat—relentless grade with no break. Save water for that push.
Recent Updates: As of June 2026, Lost Lake Trail remains open and well-maintained. No known closures or major trail work. Check the official Yellowstone website (nps.gov/yell) for real-time alerts before your trip.
Family Friendly Notes: Moderate difficulty is manageable for fit kids ages 10+. Keep children close—bear and bison encounters are real and frequent here. Hand-holding required on steeper bench segments. Stop frequently (every 20-30 minutes) for wildlife watching to break up the climb and manage pace. Teach kids to make noise and stay behind you on the trail. Not suitable for toddlers or children tired easily by elevation gain.
Nearby Facilities: Roosevelt Lodge (trailhead, historic building, ranger info, restrooms); Tower Fall Campground (~3 miles away); Mammoth District Ranger Station (~20 miles); Tower Junction has basic services. No on-trail services—all supplies must be carried in.
Review Summary: Hikers respect this trail for its moderate difficulty and guaranteed wildlife encounters. The 300-foot climb is steady but not brutal; most rate it worth the effort for Lost Lake views and waterfowl activity. Feedback centers on bear anxiety (warranted—they're here) and knee stress on the descent. Those prepared for wildlife and sun exposure praise the scenic payoff and solitude opportunities on early-start attempts.

Frequently asked questions

Will I see bears on this trail?

Very likely. This is high-bear-activity terrain—the NPS specifically warns of frequent encounters. Make constant noise, hike with a partner minimum, carry bear spray (accessible on hip, not in pack), and maintain 100+ yards distance. Bears are more dangerous when surprised; prevention is everything. If you see one, back away slowly, do not run.

Is this trail safe to hike alone?

Not recommended. While the trail is popular and well-marked, solo hiking here is reckless given bear activity. Hike with a partner minimum (groups deter bears). If you must go solo, inform a ranger of your route and expected return time, make aggressive noise, and turn back immediately if you feel unsafe.

What fitness level do I need?

Moderate. 300 feet of elevation gain over 2.8 miles is manageable for most hikers with basic cardio fitness. The challenge is not technical scrambling—it's sun exposure, relentless climbing, and psychological load of bear vigilance. Trekking poles and a steady pace help tremendously.

What gear is essential?

Bear spray (mandatory—must be accessible on your hip), 2+ liters water, sun protection (sunscreen, hat, sunglasses), map, and sturdy boots or hiking shoes. Trekking poles ease knee strain on descent. First-aid kit, insect repellent, and emergency whistle are wise. Light layers—weather can shift fast at elevation.

Can I do this trail as an out-and-back instead of a loop?

Yes. You can hike to Lost Lake from Roosevelt Lodge and return the same way (~2 miles round trip, less elevation), skipping the Petrified Tree loop extension. Perfect for time-constrained or reluctant hikers. Same scenery, lower time commitment and mileage.

How crowded is it?

Moderate-to-heavy during July-August peak season, especially 10 AM-4 PM. Weekdays quieter than weekends. May, June, September, and October are much quieter. Winter (Nov-Apr) sees minimal traffic. Start by 6-7 AM for better solitude odds even in summer.

Is there water on the trail?

No reliable potable water. A small creek near Lost Lake *may* flow in summer, but water quality is not guaranteed—filter aggressively if you draw from it. Carry 2+ liters of water from the trailhead. Dehydration is a real risk on sun-exposed sections.