Fa'side Castle (Faside Estate) has previously been known as Fawside, Falside, Ffauside, Fauxside, or Fawsyde and is a 15th-century keep located in East Lothian in Scotland. The castle is approximately 2 miles (3.2 km) southwest of Tranent, and 2 miles (3.2 km) southeast of Musselburgh. The building was restored in the 1980s and is now protected as a category B listed building.