Markham Museum is a 25-acre (10 ha) open air museum, located in Markham, Ontario, Canada. It is dedicated to the preservation of old buildings and artefacts from Markham's past. The site features nearly 30 buildings: houses, barns, sheds, a train station, a school, a general store, a church, a blacksmith, a harness shop, a saw mill, a cider mill, and many more.