Greenstone Section 5 - 3.8mi Steep Hike to Fire Tower

View of Lake, island, and lighthouse in the distance.

A short but relentless climb from Hatchet Lake deposits you atop Greenstone Ridge with panoramic views of Siskiwit Lake, Siskiwit Bay, Malone Bay, and Isle Royale Lighthouse on clear days. The trail is rooty, rocky, and narrow (18 inches wide), with overgrown vegetation and changing conditions that demand a map and compass. The payoff: Ishpeming Tower emerging unexpectedly from the forest at trail's end—a decommissioned fire tower now used for research.

Quick facts

Distance Miles: 3.8
Route Type: Out-and-back
Difficulty Level: Strenuous
Elevation Gain Feet: 520

Trail profile

Distance Miles: 3.8
Route Type: Out-and-back
Difficulty Level: Strenuous
Elevation Gain Feet: 520
Estimated Time: 3-4 hours for fit hikers; 5-6 hours if taking breaks. Factor an extra 30 min if navigating with map/compass.
Trail Surface: Rocky, rooty, narrow (18 inches). Loose stones in places. Overgrown vegetation in sections.
Trail Features: Greenstone Ridge views
Siskiwit Lake vista
Siskiwit Bay vista
Isle Royale Lighthouse view
Ishpeming Tower (decommissioned fire tower)
Old-growth hardwood forest
Ridge-top wilderness
Trail Highlights: Ascending the ridge rewards hikers with 360-degree views of Siskiwit Lake, Siskiwit Bay, Malone Bay, and the Isle Royale Lighthouse on clear days. Ishpeming Tower pops out of the forest unexpectedly at trail's end—a surprise summit that contrasts the remote, minimally maintained trail.

Trailhead & access

Trailhead Location: Hatchet Lake Campground (via ferry access from Rock Harbor, Windigo, McCargoe Cove, or private boat/water taxi to Hidden Lake)
Shuttle Required: 1
Shuttle Details: Isle Royale is accessible only by water. Options: Ranger III passenger ferry from Houghton MI (~2.5 hours), Isle Royale Queen IV seaplane from Copper Harbor MI (~30 min), or Voyageur II ferry from McCargoe Cove. Private boat or water taxi from Rock Harbor Lodge to Hidden Lake also available. Reservations required in advance for all passenger ferries.

Permits & conditions

Permit Details: No permits required for day hiking or backcountry camping on Isle Royale. However, entry fee applies ($7 per person per day).
Fees: $7 per person per day (children 15 and under free)
Trail Status: Open during park season
Seasonal Closures: Isle Royale closes November 1 to April 15 due to extreme winter weather and ice on Lake Superior.

Facilities & rules

Restrooms At Trailhead: 0
Water Sources: Hatchet Lake at trailhead (filter before drinking). No reliable water until climbing onto the ridge. Siskiwit Lake is accessible via Ishpeming Trail (if taking the alternate route to Malone Bay).
Accessibility: Not accessible. Trail is 18 inches wide, rocky, rooty, steep, and uneven. No facilities for mobility aids.

Safety & strategy

Hazards: Steep terrain and loose rocks
Narrow trail with unprotected edges on ridge
Navigation difficulty in fog
Exposure to wind
Water scarcity on ridge
Overgrown vegetation obscuring trail
Weather exposure (rapid fog, temperature drops near Lake Superior)
Hazard Details: The ascent from Hatchet Lake is steep and relentless, with loose rocks and twisted tree roots. The ridge section offers little protection from wind or sudden weather. Fog can roll in fast, making navigation treacherous without a compass. The trail is only 18 inches wide in places with no guardrails—a misstep on the ridge can be serious. Water is scarce until reaching Siskiwit Lake via the Ishpeming Trail junction. Overgrown vegetation in places obscures the trail, adding navigation complexity.
Cell Service: No cell service on Isle Royale. Bring a satellite messenger or PLB for emergencies.
Crowd Level: Ghost town. One of the quietest sections of Greenstone Ridge due to remote location, access difficulty, and steep terrain.
Peak Crowd Times: Mid-July to late August, and holiday weekends (Memorial Day, July 4th)
Best Season: June through September
Best Time To Visit: Early morning start before the wind picks up on the exposed ridge. June to September for stable weather; July-August for warmest conditions but peak bugs. Plan to summit and descend by early afternoon to avoid evening fog rolling in off Lake Superior.
Tips Advice: Wear boots with ankle support—roots and rocks twist ankles.
Bring 2-3L water (scarcity on ridge until Ishpeming).
Trekking poles mandatory for the steep descent.
Make noise for bears (though rare on Isle Royale).
Carry map, compass, and GPS—trail markers are sparse and conditions change.
Start by 7 AM to clear the trail before weather.
The false summit near Ishpeming won't look like a tower; keep going.

More details

Park Area: West end of Isle Royale National Park
Trail Markers: Minimal. Trail markers are infrequent on Greenstone Section 5. Overgrown vegetation and changing conditions require navigation skills. A compass and topographic map are essential.
Dogs Allowed: No
Biking Allowed: No
Shade Level: Mostly exposed on the ridge (no tree cover). Brief forested sections near Hatchet Lake and around Ishpeming Tower.
Emergency Contacts: Isle Royale National Park Ranger Station (intermittently staffed at Malone Bay). Alert the Hatchet Lake Campground ranger before departing. For emergencies, use satellite device or reach U.S. Coast Guard via radio if on water.
Map Recommended: 1
Mud Season: May and June can have muddy sections from snowmelt and spring runoff.
Fall Colors Peak: Late September through early October (limited hardwood species at this latitude)
Bug Season: Mosquitoes peak in June-July; black flies June-August. Bring DEET-based insect repellent.
Insider Tips: The 'summit' at Ishpeming Tower is actually a working research station, not a manned fire tower—the solitude is real.
The ridge views are worth the pain; start early to maximize daylight and clear skies.
The Ishpeming Trail junction at the tower leads to Malone Bay (7 miles)—a lesser-traveled escape route if you want a longer loop via Voyageur II ferry.
Cache water at Hatchet Lake if doing a longer backcountry push.
Overgrown vegetation in late summer (August) makes the trail harder to follow; early summer (June) is clearer.
Recent Updates: No recent major closure or reroute. Typical conditions: overgrown vegetation mid-summer, muddy sections May-June, stable July-September.
Family Friendly Notes: Not recommended for young children. The steep ascent, narrow trail, exposure on the ridge, and navigation demands make this a trek for experienced families only. Children need steady footing and comfort with heights. Hand-holding is essential in exposed sections.
Nearby Facilities: Hatchet Lake Campground (at trailhead). South Lake Desor Campground and Malone Bay Campground nearby. No resupply between campgrounds; pack all water and food.
Review Summary: Hikers consistently report that the steep, rocky ascent is punishing but delivers ridge-top views that reward the grit. The solitude is unmatched—few hikers attempt this section due to remote access and technical demands. Those who summit the tower describe the experience as raw wilderness and isolation that contrasts sharply with the crowded Rock Harbor corridor.

Location

Frequently asked questions

Is this trail safe to hike solo?

Yes, with preparation. Bring a satellite messenger or PLB—there's no cell service. Notify a ranger before departing. The trail itself is not exposed to wildlife hazard (bears are rare on Isle Royale), but navigation and weather are the risks. Solo hikers should be confident map-readers.

Do I really need a map and compass?

Yes, absolutely. Trail markers are minimal, overgrown vegetation obscures the path in places, and fog can erase visibility quickly. A GPS unit is valuable insurance, but a topographic map and compass are your primary tools.

How much elevation gain is there?

Approximately 520 feet of elevation gain over the first mile. It's steep and relentless, not spread out over gentle switchbacks. The descent mirrors the ascent.

Can I do this as a day hike from the mainland?

No. You must first get to Isle Royale (ferry, seaplane, or private boat). Ranger III ferry takes 2.5 hours from Houghton; Isle Royale Queen IV seaplane takes 30 min from Copper Harbor. Factor ferry schedules into your planning. Most day hikers arrive in the morning and depart the same evening.

What's the water situation on the trail?

Hatchet Lake at the trailhead is your source. No reliable water on the ridge until Siskiwit Lake (only accessible if taking the Ishpeming Trail to Malone Bay). Carry 2-3L minimum, more if you're slow or the weather is hot.

Is the tower worth the climb?

Yes, if you're after solitude and ridge views. The tower itself is unmanned and used for research, so there's no summit hut or amenities. But the views from the ridge and the sense of being far from civilization make it worthwhile.