Niall Iain Macdonald and Calum Macaulay take to the water as they explore the Union Canal. At the start of the canal in Lochrin Basin, Niall Iain meets Allan Maclean, who tells him all about Edinburgh's rich brewing history. Calum is learning about the history of the canal from Taobh na Pairce pupils, who are on board the Lochrin Belle. Writer and poet Aonghas MacNeacail shares his memories of the canal from his days in Edinburgh, in particular its transformation from dereliction to beautiful walkways and cycle paths today. At the Falkirk Wheel boating pond Niall Iain finds Professor Donald Meek with his scale model of The Claymore, and they remember the old MacBrayne ferries. Back in Linlithgow Calum and Niall compete in the annual cardboard boat race.