Captain Bangs Hallet House Museum in Yarmouth Port will be open May 22 from 1 to 4 p.m. with free admission as part of the Cape Cod Museum Trail’s Museum Mondays in May program. A special exhibit will show the work of the Friends of Ancient Cemetery, Yarmouth’s oldest burying ground. Volunteers have cleaned and documented 1,118 gravestones associated with 1,385 individuals in just five years. Visitors will learn how the work has been done along with a display of work of a local stone carver, data from cleaned gravestones and foil impressions made from gravestones. For more information: www.capecodmuseum trail.org or www.hsoy.org.