There is excellent walking in the surrounding countryside.
For example, a gently climbing walk from High Street (Dalintober) to Campbeltown's standing stone gives a good view over the town and Campbeltown Loch towards Beinn Ghuilean. The Kintyre Way, a long-distance walk from Tarbert in the north of Kintyre to Dunaverty Bay in the south, passes through Campbeltown. When the tide is low, you can walk out on The Dhorlin shingle causeway to Davaar Island, where there is a cave painting of the Crucifixion.
There are some good Kintyre walks described at http://www.walkhighlands.co.uk/argyll/kintyre.shtml