On the third floor of Yellowstone’s Old Faithful Inn, a snaking stairway leads 76 feet up to what seems to be an indoor treehouse. From the treehouse, a series of catwalks lead outside onto the steep roof of the inn, and stairs ascend to a deck on the very top of the roof.

This jumble of stairs and catwalks is collectively called the Crow’s Nest, designed by the then 29-year-old architect Robert Reamer. Popular belief is that he took special care to design the Crow’s Nest according to a childhood fantasy of his.

In the early days of the inn, an orchestra was hired to play from the treehouse of the Crow’s Nest, entertaining guests on the ground floor below.

Unfortunately, a 1959 earthquake that shook the park damaged the structural integrity of the inn, and the Crow’s Nest had to be closed to the public. While the damage was repaired, the Crow’s Nest has never fully opened back up to the public, albeit as much due to general safety concerns and codes. Still, the inn’s bell staff travels to the top twice every day to raise and lower the park’s flags, and regularly takes a few tourists who make reservations in advance.