Wray Castle is a Gothic looking building next to Lake Windermere. They offer guided tours of the Castle as well as dressing up and a café. It also has some stunning views and scenery to look at, with the option of getting there by boat if you wish. Wray Castle is a good place to visit on a rainy day because much of it is in doors.
Wray Castle is about 55 miles away from Castle Carrock, but it could be tied in with a visit to Hill Top (the house where Beatrix Potter lived), which is about another 5 miles away and another good destination for a rainy day.