The salt industry peaked in the mid-16th century, with about 400 salt houses in 1530, but almost died out by the end of the 18th century; the last salt house closed in the mid-19th century. Nikolaus Pevsner considered the salt-industry decline to have been critical in preserving the town's historic buildings. The last tannery closed in 1974. The town's location on the London–Chester road meant that Nantwich began to serve the needs of travellers in medieval times. This trade declined in the 19th century with the opening of Telford's road from London to Holyhead, which offered a faster route to Wales, and later with the Grand Junction Railway, which bypassed the town.