Dundas Aqueduct (grid reference ST785625) carries the Kennet and Avon Canal over the River Avon (the Somerset / Wiltshire border) and the Wessex Main Line railway from Bath to Westbury. The aqueduct is near Monkton Combe, Somerset, and is about 2+1⁄2 miles (4 km) southeast of the city of Bath. The canal crosses back across the Avon and the railway on another aqueduct at Avoncliff. This diversion onto the right bank of the Avon avoids the steep sides of the river valley at Limpley Stoke, and the need to cross the Midford Brook and River Frome.