From Oregon Hikers Field Guide
The Stone House, also fondly monikered the Witch's Castle, is located at the junction of the Lower Macleay Trail and the Wildwood Trail.
It was built by the City of Portland in 1929 as a rest station with bathrooms and running water (In their guide to Portland "oddities" PDXccentric, Scott Cook and Aimee Wade debunk the myth that the structure was created by either the CCC or the WPA) . It suffered from repeated vandalism, and during the Columbus Day Storm of 1962 received severe damage to the plumbing and roof from toppled trees. The city decided not repair the building, and instead removed all the fixtures, doors and roof. All that remains is the stone framework.
Near here, just down the Lower Macleay Trail, is the tallest tree in Portland, a 242-foot high Douglas-fir.