Construction of the locks on the Leicester line of the Grand Union Canal started in 1810 and were completed in 1814. Comprising two staircases each of five locks, this is the largest flight of staircase locks in England. The locks use side ponds to conserve consumption of water.

In 1900 an inclined plane was built parallel to the locks to speed up the passage of boats and to permit the passage of wide-beam barges.

The "Thomas" Lift was designed by Gordon Thomas and had two tanks or caissons, each capable of holding two narrowboats or a barge. The caissons were full of water, and so balanced each other. The lift was powered by a 25 horsepower (19 kW) stationary engine.

The inclined plane had a journey time of twelve minutes for two boats up and two down and improved the speed of passage up the hill tremendously. Unlike the locks, where water flowed downhill every time a boat passed through, on the inclined plane almost the same amount of water went up and down the hill. As only the displaced water is moved, there is an appreciable saving.

There was a plan to build a similar inclined plane at the Watford Locks at the southern end of the canal's summit level. However, this was never carried through, and as the Watford Locks were never widened, the economic benefits of the plane could not be fully realised. Thus, despite its obvious effectiveness, the Foxton Inclined Plane was mothballed in 1911 to save money. After that date it saw occasional use when the locks were undergoing maintenance.

In 1927, dismantling of the incline began, so that it could be sold for scrap. That year the chimney on the engine house was demolished and its bricks used for various canal repairs.

The remains of the plane can still be seen and partly explored by visitors. In the building alongside the locks, which is the former boiler house for the plane's steam engine, there is a small museum covering the history of the locks and the plane, and other aspects of the local canal. The mooring bollards from the incline can be found alongside the locks. The clearing of the site and restoration of the canal arms above and below the plane was completed in 2008, removing the site from the Monuments at Risk Register. The swing bridge over the Harborough Arm, which allowed horses to tow their boats to the lift, has been replaced with a new bridge based on the design of the original. The Top Arm has been re-excavated to the original profile and re-watered.

The locks are Listed Grade II* and the site of the Foxton Inclined Plane Boat Lift has been recognised as a Scheduled Ancient Monument and was on the Monuments at Risk Register. This recognition, together with the steady increase in leisure boating on British canals, means its restoration is now considered a key project in the development of the national waterway network. In 2008, the complex became part of the European Route of Industrial Heritage.

Also see Caen Hill / Devizes Locks on the Kennet & Avon Canal