The Trent-Severn Waterway links Georgian Bay with Lake Ontario through a series of 45 locks. The route is 386 km long (240 miles) beginning with Lock 1 at Trenton and ending at Lock 45 at Port Severn on Lake Huron's Georgian Bay. Two of the locks located at Kirkfield and Peterborough are hydraulic lift locks. The locks rise 182 metres at Balsam Lake and then drop 80 m to Lake Huron.
Originally the waterway was planned as a military route. By the time the first locks were constructed in 1833 the threat of war with the U.S. had diminished and the locks, which were built in stages from 1822-1920 were used primarily for commercial use.
In 1972 Parks Canada overtook the operation of the Trent-Severn Waterway and today it is used as a recreational waterway. The Trent-Severn Waterway is a National Historic Site of Canada and has been referred to as "one of the finest interconnected systems of navigation in the world".
Region 1: Southwest Ontario • Region 2: Niagara Canada • Region 3: Hamilton, Halton and Brant • Region 4: Huron, Perth, Waterloo and Wellington • Region 5: Greater Toronto Area • Region 6: York, Durham and the Hills of Headwaters • Region 7: Bruce Peninsula, Southern Georgian Bay and Lake Simcoe • Region 8: Kawarthas and Northumberland • Region 9: South Eastern Ontario • Region 10: Ottawa and Countryside • Region 11: Haliburton Highlands to the Ottawa Valley • Region 12: Muskoka, Parry Sound and Algonquin Park • Region 13a: North Eastern Ontario • Region 13b: Sault Ste. Marie – Algoma • Region 13c: Northwest Ontario