Vikingsholm is a 38-room mansion on the shore of Emerald Bay at Lake Tahoe, in El Dorado County, California, U.S., and on the National Register of Historic Places.

While Mrs. Knight is known for building Vikingsholm, she and her businessman husband Harry were also primary backers of Charles Lindbergh's non-stop solo flight across the Atlantic Ocean in 1927.

[3] Harvey West, a wealthy lumberman who owned the land after Knight, sold it to California for half of the appraised value in 1953.

"[4] Vikingsholm, along with Knight's "Tea House" on Fannette Island, is a part of Emerald Bay State Park, which has been declared a National Natural Landmark.

In addition to the buildings, some of the rock retaining walls, the water tanks, and the entrance from the highway were also constructed during the time Mrs. Knight owned the property.

Pine and fir siding with ornamental handcarvings cover the wall surfaces, or they are exposed stone.

Originally, it had a flat roof, a door, and windows, but these were destroyed by vandalism and now only the main stone structure remains.