There will be no charge for tours of the John Strong Mansion Museum on August 18. The John Strong Mansion Museum is a historic house museum located at 6656 Vermont Route 17W in Addison, Vermont. It was built in 1795-96 by John Strong, a Vermont politician and veteran of the American Revolutionary War. It is one of Vermont's grandest examples of late 19th-century Federal architecture. It is now operated as a museum by the Daughters of the American Revolution, open between Memorial Day and Labor Day. It is surrounded by D.A.R. State Park.