Thirsk is built around a large medieval market square, which still hosts an open-air market each Monday and Saturday. The market was established in 1145 and is the focal point for local farmers, traders and visitors. The town was once known for its leather tanning and saddlery trade, but this was replaced in the 19th century by the production of farming implements. This was aided by the establishment of the Mechanics Institute in 1848. Copied from the entry in Wikipedia.

Postcard of Thirsk Market Place
(allegedly from the NW but, based on Google Maps Satellite View, it appears to be from the SE corner at Millgate)
Postcard of views in Thirsk
(Left is Kirkgate, top right is St Mary's Church, bottom right is the Market Place, apparently taken from the NE corner)