
The couple travelled along the waterway in a Seagull Trust boat before unveiling a plaque beside the 30-metre (90 feet) Kelpie sculptures.
The Canal Project which is now named the Queen Elizabeth II Canal is aimed to make Scottish canals navigable for the first time in 50 years, while the Kelpies form part of the 43 million pound ($55.5 million) Helix project creating a community green space near Falkirk.