Dartmouth's deep-water harbour has been strategically important for centuries, from Crusader departures to D-Day operations. The town climbs steeply from the waterfront, with colourful houses tumbling down hillsides and narrow streets revealing independent shops and cafés. Dartmouth Castle guards the harbour entrance, the Royal Naval College dominates the skyline, and boat trips up the River Dart to Totnes offer beautiful scenery and glimpses of Agatha Christie's former home at Greenway.