Lake Creek Bridge, also called the Nelson Mountain Bridge, is a historic covered bridge near Greenleaf, Oregon. Built in 1928, the 105-foot structure carries Nelson Mountain Road over Lake Creek and is listed on the National Register of Historic Places. It is distinguished by upper and lower truss chords made from single-piece old-growth timbers, narrow ribbon windows at the eaves, and portals formed as truncated rectangular arches. A 1984 renovation added reinforced concrete abutments, new flooring, and other modifications to increase load capacity and keep the bridge in service.