Constructed in 1449, Mearns Castle is a Category A listed building situated in the suburban Glasgow town of Newton Mearns. Constructed by Herbert Maxwell (1st Lord Maxwell), historic records suggest it was used as a place of visit for his family, who resided at Caerlaverock Castle in Dumfriesshire, rather than a place of permanent residence. The site sits on a prominent position that maintains a view of the surrounding area.

The building consists of a single rectangle-shaped tower with four stories. The main entrance is an arched-stone feature on the first story and historically was accessed by a ladder. The castle remained in the Maxwell family until it was sold in the 17th century and after several ownerships, the castle began to fall into a state of disrepair. 

It was later restored and now forms part of the Maxwell Mearns Castle Church, although the castle itself is mostly unused.