Some visit, I highly recommend touring Blithewold in Bristol, a beautiful mansion on the water.

A mother and daughter who lived there spent their lives bringing rare trees from their travels around the globe to plant there, like their own private arboretum. You can tour inside too.

Best times to go are around Christmas when they have events, or my favorite: springtime, when tens of thousands of daffodils bloom in their "bois" (lightly wooded areas). Idyllic.