When the London and Birmingham Railway reached Euston in July 1837, the last mile had an incline of 1 in 85 and there was concern that it was too steep for locomotives of the time. As a result, two stationary steam engines were installed in a vault beneath the track which hauled trains up the incline via a 3.5 km continuous rope. Coal for the engines was supplied from the adjacent Regent’s Canal via a tunnel. The cable haulage was replaced by locomotives in 1844 and the machinery removed; two locomotives were often used for heavier trains. The vaults still exist beneath the current trackbed and are now Grade II* Listed. Because of the nearby canal, the vaults are usually flooded but they are pumped dry every six years or so for a regular inspection.