We are north Wiltshire, Marlborough/Devizes area and don't particularly want to drive for more than 1.5 hours each way. We have ds1 who is 3.4 and ds2 who is 16 weeks. On the list is Cotswold wildlife park, Bristol aquarium & SS Great Britain, Brokers Wood country park, as well as a few nice walks weather permitting! But wondered if you had any other ideas?