Edward E. Hartwick Memorial Building, Hartwick Pines State Park

M-72–Au Sable River Bridge, Grayling

160 min walk • The M-72–Au Sable River Bridge, also known as the Grayling Bridge or State Street Bridge, is a bridge located on M-72 over the Au Sable River in Grayling, Michigan. It was listed on the National Register of Historic Places in 1999.