Normally there wouldn't be a market, but since the festival is there I think we can say that there is a makeshift one.

Sarnath would be one of those villages where it is small enough that if people want to buy shit, they just go to the person who has it in town and make a trade. 

Though the town itself would be shitty and dull, the Castle would definitely be pretty impressive, being Visha built and all.