Sourdough Mountain Lookout, on the summit of Sourdough Mountain in North Cascades National Park, is a historic fire lookout built in 1933 by the Civilian Conservation Corps to replace an earlier 1917 structure. Added to the National Register of Historic Places in 1989, the square cabin was designed with shiplap siding, a wood-shingled hip roof, and shutters that opened in all directions for fire spotting. Though no longer regularly used for that purpose, it remains a hiking destination and is closely linked to mid-20th-century American poetry through the work of Gary Snyder and Philip Whalen, who both served there as lookouts and wrote influential poems inspired by the mountain.