Work started almost immediately on the level ground from Preston to Tewitfield, and in 1794 on the Lune Aqueduct, which was built of stone, although Rennie thought brick should have been used, as it would have been considerably cheaper. By 1797 the aqueduct was open, carrying the canal above the river, and boats were now able to travel the from Preston to Tewitfield. In 1813, work began on the canal north from Tewitfield, which was completed to Kendal in 1819. Construction on the Glasson Dock branch began in 1819, and it opened in 1826, with six locks carrying the canal down to the sea.