U.S. Route 8 descends through the Minnesota park in a road cut blasted in 1931. The Minnesota Department of Transportation built stone overlooks and guardrails along the highway in the mid 1930s. Civilian Conservation Corps Company 633 arrived in 1935, building roads, trails, picnic grounds, plumbing, the beach and beach house on Lake O' the Dalles, and retaining walls. The CCC camp departed in December 1937 and were replaced by the 4610th Company of the Works Progress Administration in July 1938. They are considered significant as examples of New Deal federal work relief, early state park development, National Park Service rustic design, and—in separating the intensive use of camping and picnicking from the open-air museum of the Glacial Gardens—landscape architecture.