Hallam Lake, a 25-acre nature preserve and environmental learning center, was the first location of Aspen Center for Environmental Studies. The property was donated in 1968 by Elizabeth Paepcke when she founded ACES. The preserve is open to the public year-round and provides an inspiring setting for ACES’ many educational and naturalist programs. Hallam Lake is home to resident birds of prey and lush riparian ecosystems including woodland, meadow, pond and marsh communities. We invite you to explore this beautiful and unique preserve.
A half-mile loop nature trail is available for all visitors. This trail meanders in and out of wetlands and includes stops at various observation decks. On any given day, a variety of birds and mammals can be seen feeding at the water's edge. During the day, swallows perform acrobatics above the water in search of insects, while the American dipper dives underwater in search of aquatic insects. As the sun sets, fox, bear, and deer prowl the banks searching for dinner, while beaver cautiously feed on willow, aspen, and cottonwood bark around the lake.