[1][2][3] It runs under the hill that was once the site of Reigate Castle and was built during 1823, although some sources report that it only opened in 1824.

[7][8] It is 51 m (56 yd) long[9][10] and runs through the Folkestone Beds beneath Reigate Castle.

It provides a direct link between the High Street (to the south) and London Road (to the north), reducing the distance between the two by 0.25 mi (0.4 km).

[8] Construction began in 1823 and required the demolition of two shops on the north side of the High Street.

[7] The work was funded by John Cocks, 1st Earl Somers, through whose land it ran, and was completed in the summer of 1824.