Cirque

High in the mountains, at the head of an alpine valley, is a large bedrock basin – a cirque. This marks the birthplace of the glacier that once filled and sculpted the entire valley. The cirque has a tilted-bowl interior shape, with the low lip of the bowl being a rock threshold leading down further into the valley. All other sides of the cirque are enclosed by high, steep rock walls. The center floor of the cirque is lower than the lip, containing a cold pond (tarn) with a striking aqua or emerald green color. The sense that this pond hangs on the edge of the sky can be very strong, until you walk right to the lip and look down out of the cirque to see the valley floor falling away below.

Dimensions The cirque floor is about a thousand feet (300 m) across, maybe twice as long running from the cirque lip directly across to its head. While the tarn is 600 feet (180 m) across, it is fairly shallow and water depth at center is only 20 feet (6 m). The surrounding walls, a mix of cliffs and steep slopes, tower 500-1500 feet (150-450 m) above the tarn.

Key Details

Talus above cirque lake, Rocky Mountain National Park, Colorado.

The high rock walls on most sides of the cirque severely limit an occupant’s view of the sky: storms coming from many points of the compass can be nearly overhead before being seen.
Daytime weather conditions in the summer months may be: 1) still and peaceful, with cool air and pleasantly sun-warmed rocks, 2) windy and unwelcomely chilling after a long, hot trek up-valley, or 3) stormy with lightning, chilling rain and sleet. All of these typically occur each day, often in quick succession.
In winter, the tarn will be frozen and the entire cirque floor covered with snow drifts of varying depths. On fairly clear days, the cirque floor will still receive sporadic showers of dry snow carried by wind off adjacent highlands.
If there is any small, near stagnant remnant of a glacier in this valley, it will be on the uphill side of the tarn, or higher on the cirque back wall. It may appear to be simply a large snow bank in early summer, but by early autumn some bare, dirty glacial ice should be evident on the lower part of the glacier surface.
Some cirques have smaller cirques (sources of past ice tributaries) that hang higher on the surrounding rock walls. Only the outer lips and indented upper head-walls of these small cirques are visible from the main cirque floor.
The cirque floor is broad and open, with no vegetation high enough to provide cover. Scattered boulders and rock knobs provide some spots to hide from others within the cirque, but no concealment from observers situated higher up on the cirque walls.
Climbing from the cirque floor to surrounding ridge tops requires scaling sheer cliffs in many places. More moderate slopes on some cirque walls allow the climb to be made by a long up-slope scrabble over loose rocks and through snow banks. If there is a part of the back cirque wall with a noticeably lower crest than adjoining walls, that crest is likely razor-sharp – a place where this cirque’s upper edge has joined with the steep back wall of another cirque on the opposite side of the mountain ridge – not a good route to the real high ground.

Cirque headwall, Rocky Mountain National Park, Colorado.

Story Elements

A chase might naturally end here, as enclosing rock walls leave nowhere to run.
The most likely way to reach this spot is by many hours of hiking, and occasional clambering, up the valley on foot. In summer, the trek can be hot and dusty, but what seems like a cool resting place at trip’s end may soon be chilling if the wind kicks up or clouds appear, so that the hikers may not want to linger long.
Birds and mountain goats might frequent this spot to drink.
The translucent, green waters of the tarn might hide a treasure, or be home to an unexpected type of water creature.
One of the smaller, tributary cirques may serve as a lookout or sniper station, place for a signal fire, remote hiding place for something precious, or roost for a creature.
This is an environment where many characters will likely need to do dangerous and exhausting climbing to accomplish their goals (whether that is escape, a sought object or realization, meeting with someone arriving from above, or lighting of a signal fire).
Visitors who know the area well will likely plan their activities to avoid, or take advantage of, the weather changes late in the day (such as late afternoon storms that clear away quickly).
Someone hiding beneath fallen boulders on the cirque floor, with limited range of view, might still see some additional areas of ground or sky as reflections in the tarn surface, so long as it stays smooth. (Gusts of wind could temporarily interrupt this view.)
Natural flow and melting of a small remnant glacier in the cirque could expose something that was encased in the ice for decades or centuries. Similarly, a rock carving or some other solidly placed artifact may have been intentionally located on bedrock at the foot of the glacier, where it is covered by winter flow of the ice, and only revealed when the glacier front melts back in late summer. Flow rate of the glacier might be accelerated or arrested by magic or technology.
Combat dynamics:
- The lip of the cirque provides a natural defense line against attacks from further down-valley, or to keep something in the cirque from having access to the greater world.
- Snipers on high ridges above, or in tributary cirques, may have huge advantage because of the lack of cover on the cirque’s open floor. An attack from the sky could have a strong element of surprise.
- The tarn makes the dry cirque floor a doughnut-shaped combat arena for melee fighting. There may be a distinct advantage to those with distance weapons, or those with ability to quickly traverse water.

Reference Location

Rocky Mountain National Park, north-central Colorado. Several different cirques are reached at ends of hiking trails that start from the area around Bear Lake, and travel to the cirques via alpine valleys (see Alpine Valley scene description). Nearby within a mile (2 km) or less, at tops of the steep valley/cirque slopes, are broad upland areas detailed in the Highland Tundra scene description. Similar cirques and other glacier-sculpted mountain topography can be found elsewhere in the Rocky Mountains, and in high mountain ranges across the world.