Avon Aqueduct
Lowlands
This 12-arch structure built by Thomas Telford is the second longest in Britain - only beaten by the Pontcysyllte Aqueduct on the Llangollen Canal. Unusually, the metal trough construction features a towpath on either side. Two miles to the east is Linlithgow and the Linlithgow Canal Centre (01506 671215) with a museum devoted to the Union Canal, tea room and gift shop. Boat trips operate from here to the aqueduct (departure times and tickets from the museum).