Galle is Sri Lanka's premier tourist destination. Tourists are mostly British with a sense of nostalgia for a colonial past or simply escaping a European winter; unfortunately hotel prices reflect the strong EU currency; cheaper options will be staying at Unawatuna or Ahangama or better still Mirissa (best beach by far) a stones throw away from Galle. Galle fort is a world heritage listed site and a true reflection of Sri Lanka's recent colonial history; foundations built by the Portuguese in the 14th Century, completed by the Dutch and occupied by the British.
Like Sigiriya, Galle fort is a "must see" Sri Lankan destination!