Neptune’s Staircase at Banavie, near Fort William just north of Loch Linnhe, is kept by Scottish Canals.

[1][2][3] The current lock gates weigh 22 tons each, and require a team of at least three lock-keepers to operate the staircase.

Prior to mechanisation, the locks were operated by capstans, each with four poles, which had to make seven full revolutions to open or close a gate.

With the advent of hydraulic rams and push-button control, transit times through the flight have been reduced from just over half a day to 90 minutes.

The Caledonian Canal was conceived by the engineer Thomas Telford after the government asked him to look at measures which might stem emigration from the Highlands.

James Loch, who produced a report on the canal in 1835, declared that the inn at Banavie was too small, and too far from Corpach, despite having praised it the previous year.

He described the masonry as "execrable", and argued that the contractor who had built them had not expected them ever to be used, but had somehow managed to hide the poor workmanship from Telford.

By the end of the First World War, the canal was in serious financial difficulties, with maintenance costs far exceeding revenue, and in 1920 the Ministry of Transport made a grant of £11,000 for major repairs to the Banavie locks.

A further stoppage of three months occurred in 1929, when a Drifter (fishing boat) broke through two of the Banavie lock gates, causing flooding.