Clyde, River, is the chief commercial waterway in Scotland. The River Clyde rises in the Southern Uplands of Scotland and flows northward for 100 miles (160 kilometers). It empties into the Firth of Clyde, an inlet of the sea along the west coast. The Falls of Clyde near the town of Lanark once furnished the power for many mills in the Lowlands. Shipbuilding yards once lined the river’s banks in Glasgow, Scotland’s largest city. The Queen Mary, Queen Elizabeth, and other famous ships were built there. Below Glasgow, the river widens into the Firth of Clyde, which is over 50 miles (80 kilometers) long.