One of the closest hiking trails to Sudden Valley is at The Stimpson Family Nature Reserve. It has about 4 miles of hiking trails through a beautiful forest setting and meanders past two ponds that support a wide variety of plants and animals. The Reserve is a combination of the 138-acre Lake Louise Natural Resources Conservation Area owned by the Department of Natural Resources, 196 acres owned by Whatcom Land Trust and 34 acres jointly owned by the City of Bellingham and Whatcom County.

A large part of the Stimpson Family Nature Reserve was donated to the Whatcom Land Trust in 2000 in memory of Edward K. and Catharine C. Stimpson by their seven children.