The Lagan Navigation
In the late 19th century the Lagan Navigation was built from Lough Neagh to Belfast, using some of the river as a navigable waterway and diverting water from other areas to supply separate canal sections. However by the mid-20th century the route had fallen into disuse and was largely derelict. The M1 motorway (Northern Ireland) was built across the route. Currently, the section of the navigation's towpath running from Lisburn to almost the centre of Belfast has been restored.
Read more about this topic: River Lagan