The Lancaster Canal was built from old Ashton Basin in Preston to Canal Head in Kendal, a distance of 57.0 miles (91.8 km) with 8 locks. At present the northern reaches of the Canal (Tewitfield to Kendal - 14.6 miles - 23.4km - 8 locks) are derelict with restoration proposed, and a short section of the canal in Preston is also derelict. There is a branch to Glasson - 2.9 miles - 4.4km - 6 locks plus a tidal sea lock, and the Ribble Link joins the main line 1.5 miles (2.4km) out of Preston.
The maximum size of boat that can navigate the Lancaster Canal is
length: 77' 11" (23.75 metres) - Lock 2 Glasson Branch (no structural length restrictions on the navigable main line). Tewitfield Locks (under restoration) are 72' 0" (21.9 metres) long.
beam: 16' 0" (4.88 metres) - Bridge 79 (Cockerham Road Bridge)
height: 8' 2" (2.50 metres) - bridge at Lock 2 Glasson Branch
draught: 4' 6" (1.37 metres) - cill at Lock 2 Glasson Branch
The Sea Lock at Glasson is operated by Lancaster Ports Commission.