Tammany, or Mount Tammany, is a historic home located at Williamsport, Washington County, Maryland, United States. It is a two-part brick structure resting on low fieldstone foundations. The main block is a two-story, three-bay structure with a side hall entrance. Attached to its north gable wall is a two-story five-bay structure also of brick. The house features a one-story porch with a low-hipped roof, supported by round Doric columns. It is believed to have been built in the 1780s by Matthew Van Lear, a prominent early resident of Washington County. It was listed on the National Register of Historic Places in 1979.