The original spelling seems to have been Caldwall, but it is often spelt Caldwell. This octagonal medieval tower is all that remains of what was Caldwall Castle. This was probably not so much a castle as an upper floor hall house, with the tower in its centre. The rest of the building was rebuilt around 1690 as Caldwall Hall. That was demolished in 1961, leaving the 14th century tower surviving. The windows are mostly 17th/18th century, except for the small openings in the northwest stair-turret, which are thought to be mid-14th century. They can be seen in this view. The building is believed to be the oldest surviving secular building in the town. The building behind is the Fire Station.