A rewarding way to experience the River Dart is to join a cruise from Dartmouth's quay to visit Greenway, the 16th-century riverside home of the Gilbert family (Sir Humphrey Gilbert claimed Newfoundland on behalf of Elizabeth I), more famous today for its association with the crime writer Agatha Christie. Mrs. Mallowan (Christie's married name) made it her holiday home beginning in 1938, and the house displays collections of archaeological finds, china, and silver. The gorgeous gardens are thickly planted with magnolias, camellias, and rare shrubs, and richly endowed with panoramic views. Beware, however, that the grounds are steeply laid out, and those arriving by boat face a daunting uphill climb. Allow three hours to see everything; timed tickets for the house are given on arrival. Parking spaces here are restricted and must be booked in advance. Alternatively, ask at the tourist office about walking and cycling routes to reach the house, as well as a vintage bus service from Torquay and Brixham. A round-trip ticket between Dartmouth and Greenway costs £8.50 on Greenway Ferry Pleasure Cruises (www.greenwayferry.co.uk), which also operates a vintage bus service to Greenway from Torquay, Paignton, and Brixham.