The Ulster Canal is a disused canal running through part of County Armagh, County Tyrone and County Fermanagh in Northern Ireland and County Monaghan in the Republic of Ireland. In the early 19th century the idea of linking the lowlands around Lough Neagh with the Erne Basin and the River Shannon system became popular with the more progressive landowners and merchants of Armagh, Monaghan and Fermanagh. The Ulster Canal was built between 1825 and 1842 and was 74 km (46 mi) long with 26 locks. It ran from Charlemont on the River Blackwater to Wattle Bridge on the River Finn, south-east of Upper Lough Erne. It was an ill-considered venture, with the locks built narrower than the other Irish waterways, preventing through trade, and an inadequate water supply. It was an abject failure commercially, and contributed to the collapse of the Lagan Navigation Company, who took it over from the government but were then refused permission to abandon it when they could not afford the maintenance costs.