Headstone Manor is an unlikely survival: a genuine medieval manor house, surrounded by a water-filled moat, sitting in the middle of a suburban park. The main hall dates from around 1310, making it among the oldest timber-framed buildings in the county. The site includes a 16th-century tithe barn — one of the largest surviving examples in Middlesex — which now houses the Harrow Museum's main exhibition space covering the local history of the borough.
The museum's collection is well presented and covers the area from prehistoric times through to the postwar suburban expansion that transformed Harrow from a small market town into a commuter borough. There are regular events and temporary exhibitions. The grounds are open as a public park and include a recreation area, making this a reasonable destination if you have children in tow. The manor itself is accessible on guided tours; the museum and grounds can be visited independently.