For lots of useful information about the area, activities and things to see and do, see:
There are a number of interesting places nearby owned by The National Trust for Scotland and Historic Scotland, which have reciprocal arrangements with the National Trust and English Heritage provided you show your membership card on entry. These include Brodie Castle, Culloden, Fort George and, a little further afield, Inverewe Gardens. Other castles worth visiting are Cawdor and Dunrobin.
There are also plenty of things to do in and around Inverness.