Situated to the south of Loch Lomond and 3 miles (5 km) north of Dumbarton on the west bank of the River Leven, Alexandria developed from a simple grocer's shop established on the site in the early 18th Century. It expanded to form an industrial town with a narrow north-south street plan that eventually connected with the nearby villages of Balloch, Jamestown and Renton. In 1836 a bridge over the Leven linked Alexandria with Bonhill, and the result is now a significant conurbation. Bleaching, dyeing and printing brought early prosperity to the town and between 1905 and 1913 the Argyll Motor Works was the largest car production plant in Europe. The factory, later used by the Admiralty to produce torpedoes, now houses the Loch Lomond Galleries Shopping Centre. Now largely a commuter settlement with rail links to Glasgow, Alexandria's textile industry has been replaced by whisky distilling and light industry on the Vale of Leven Industrial Estate.
Alexandria benefits from four primary schools and, at the south of the town, is the Vale of Leven Academy. There are railway stations at Renton, Alexandria and Balloch, with trains to Dumbarton and on to Glasgow.
The town is named after Lieutenant-Colonel Alexander Smollett, who died in 1799 at the Battle of Alkmaar, while novelist Tobias Smollett was born nearby at Dalquhurn House in Renton. The long-demolished Place of Bonhill was built in 1642 for the Smolletts but became the home of the Turnbulls from 1762 when the Smolletts moved to Cameron House on Loch Lomond.