The Town Council looks after a number of historic buildings in the town. It leases Hertford Castle, a Grade I listed building and owns the Seed Warehouse in Maidenhead Yard, a Grade II listed building.

The Town Council bought the seed Warehouse in 1983 and at the moment Hertford Museum uses most of the ground floor for storage and to house the Roman corn-drying oven found during excavations at Foxholes Farm in 1975. The Seed Warehouse also houses the Mill Bridge Rooms which are let to local organisations for meetings and events, and offices rented by local businesses.

In 2003, while divers were investigating the river bed in preparation for building the new bridge between Nicholas Lane and Maidenhead Yard, they discovered that the river had scoured a hole beneath the Seed Warehouse. Specialist engineers were engaged to design a scheme for the repairs essential to ensure the future of the building, and this work has now been complete.