If history is your thing make sure you have sufficient time at Nelson's Dockyard - a delight. Do not wander away from the tourist areas - some of the residents can be a bit intimidating - be vigilent at all times..
Fantastic beaches - we had a glorious time on Eagle beach a $2 return bus ride from the cruiser dock. Don't be tempted by more costly taxi rides to other commercial developments on other beaches.
We took a personal guide around the island which is beautiful with beaches alongside the active volcano in the north. Friendly people wanting to sell you a cool drink on the beach - heaven. Beware the water taxi from the cruiser dock - they transfer hundreds of passengers to the local beach which can not accommodate the numbers arriving.
The real gem of the caribbean islands but head for the french side - spend a pleasant hour in Merigot and then visit Orient beach for a chill out session. Superb - we can't wait to return.