The Eden Project, Cornwall

The Eden Project is a series of domes set in an old slate quarry. Inside the domes are two major environments: a tropical rainforest and a Mediterranean dry area. The environments are well laid out, taking you progressively through different features of the two environments. It takes about four hours to go round both the domes and the exterior gardens. If you are in Cornwall it is worth a visit, but arrive at 10am to avoid the queues - this is a popular attraction!