Welkinweir is a 197-acre arboretum, garden, mansion, and conservation area in East Nantmeal Township near Pottstown, part of the Hopewell Big Woods. Once the home of Everett and Grace Rodebaugh, founding members of the Green Valleys Association, it was developed over decades after they bought it in the 1930s. Their 1940 house, designed by Fridtjof Tobiessen, incorporated parts of earlier houses dating to about 1750 and 1830. The grounds contain diverse tree and flowering collections, including cherries, dogwoods, magnolias, maples, sweetgum, azaleas, and rhododendrons. Protected by a conservation easement in 1976 and donated in 1997, it became the association’s headquarters and educational center and joined the National Register of Historic Places in 2001.