El Capitan Cave on Alaska’s Prince of Wales Island, known as El Cap to its natives, is the largest known cave in Alaska, and is also the first cave in Southeast Alaska where fossil bones were discovered – dating back to over 12,000 years ago. The only way to see this magnificent cave is during the summer months, when visitors can take advantage of a no cost guided tour given by Forest Service employees.
El Capitan features the deepest limestone pit in the United States. The cave entrance faces south across the shallow El Capitan Passage, providing a nice view of Kosciusko Island. It is also located above the El Capitan Forest Service Camp, which gets its water from a spring that emerges below the cave (and ultimately from a river inside the cave).
A variety of wildlife uses the El Capitan Cave for shelter. River otters follow a scent trail to find their den in the darkness. Otter tracks are sometimes visible and their fur can be seen on the gate. Two species of brown bats seek shelter in the cave during the winter. Small cave-adapted organisms such as amphipods, collembolans and mites are found in the small pools.