Green Lake lies at the base of Pagoda Mountain in the southeast corner of Glacier Gorge. A popular trail leads 4.8 miles to Black Lake, past which a rugged x-country route continues 1.3 miles in a spectacular alpine landscape to Green Lake. Anticipate steep, ill-defined conditions past Black Lake and plan travel time accordingly:

The Loch Vale Trail rises steadily through young aspen and mixed pine to Alberta Falls (.85 miles : 9,423'). A moderate climb continues to the North Longs Peak Trail split (1.6 miles : 9,768'), where it banks southwest and flattens through a narrow slot between Thatchtop Mountain (12,668') and the Glacier Knobs.

The trail drops to Glacier Junction and bears left to Mills Lake (2.1 miles : 9,804').

The trail turns south, crossing Glacier Creek twice and sections of cairn-marked rock slabs to Mills Lake (2.65 miles : 9,955'). Here you'll enjoy terrific views of Glacier Gorge and the jagged ridges and peaks that define it.

The trail - now intermittently rugged, undulating and heavily rooted - follows the lake's east shore to its marshy juxtaposition with Jewel Lake (3.1 miles : 9,967').

It continues past Jewel Lake through a string of marshes aided by narrow, elevated planks. A cluttered forest reclaims the trail (3.2 miles), which closely follows Glacier Creek all the way to Black Lake.

Anticipate steep undulations and occasional loss of clarity over the next 1.5 miles; when in doubt, simply hold your line and follow the creek. You'll pass the Glacier Gorge Backcountry Campsite spur (3.35 miles : 10,068') and scale newly built stairs. Travel intensifies in a thick forest to a cairn-marked rock slab (3.85 miles : 10,205'), then moderates across a meadow with good views of the upper gorge (4.1 miles).

The Arrowhead (12,387'), Powell Peak (13,208) and McHenrys Peak (13,327') frame the west, while Pagoda Mountain (13,497') and Keyboard of the Winds - a line of pinnacles near the summit of Longs Peak - rise to the east. Chiefs Head Peak (13,579') and The Spearhead (12,575') cap the upper valley.

Uneven travel continues to the base of Ribbon Falls (4.7 miles : 10,540'), which spill from the north shore of Black Lake. The trail twists steeply beside the falls and hops a line of flat boulders across the outlet to Black Lake (4.8 miles : 10,630'). It scales a small knoll to the east shore (4.85 miles), where you'll turn east and begin a strenuous climb up Black Lake's inlet into the tundra.

The initial climb follows a well-defined path beside the inlet with exceptional views of the cirque below. It reaches an unmarked fork at 5.15 miles (11,980'), where some map depictions of a clear path east of this stream belie the actual landscape before you. Though you'll trace this stream all the way to Green Lake, you'll necessarily favor its west side, as the east side is generally unsuitable for efficient travel.

Bear right at this fork and cross the stream to regain the trail. It threads dense willow and large boulders to a second, more precarious stream crossing (5.27 miles); once through it levels in a sprawling alpine terrace of rock slabs, meadow, ponds, boulder fields and streams. The on-off again trail is gradually absorbed by it, leaving navigation to a good map, eye and intuitive read of the landscape. Cairns offer guidance, but note that many run off to climbing routes, improvised campsites or simply nowhere in particular.

The trail follows the stream into the valley's southeast corner, its origin - and your destination - increasingly clear. The final approach crosses a perennial snowfield and squeezes through a narrow chute that levels on the rocky shore of Green Lake (6.15 miles : 11,555'). A relatively mild climb leads above Green Lake to a small tarn at the foot of Pagoda Mountain.