What do you think Hitchin is most famous for?

It could be for several reasons. The hisoric buildings i.e St Mary's Church. Being the birthplace of many famous people? I do know that there have been a lot of actors that have originated from Hitchin.

Aren't you forgetting Hitchin's MOST famous resident?I'm talking about Sir Henry Bessemer(1813-1898).He was the inventor of the Bessemer process,used in the manufacture of steel.