[1] The building is a two-storey structure built from sandstone ashlar, fronted by a projecting tetrastyle Tuscan portico.

The cupola surmounting the building has a square base with a second octagonal stage on the side of which is a clock face.

[2] The ground floor was originally open and contained an arcade housing a market for grain and butter.

It depicts a Roman soldier on horseback with a decapitated opponent at his feet, and is described as "an iconic piece of Lancaster's dramatic past [giving] a crucial insight into the history of the county.

"[4][5][6] The museum was also successful in acquiring the Viking-era Silverdale Hoard, discovered in the City of Lancaster district in 2011, for its collection.