Activities include broadsword demonstrations, archaeological investigations, tours of the strong rooms, a quiz to identify medieval artefacts and an armour conservation lab where children can make their own helmet and shield.
The event runs from 10am until 4pm on Saturday, September 25 and entry is free.
Children are invited to come in medieval costume, with a prize for the best one.
The Wiltshire and Swindon Archives, which is based in Cocklebury Road, Chippenham, contains thousands of historic documents about the county.
Friendly and knowledgeable staff will also be available to answer questions on local and family history.
For further information call (01249) 705500
Source: Gazette and Herald