Single locks (also known as narrow locks) have just one lock gate and are the most straightforward to use. They are designed for a standard 7ft wide narrowboat. You’ll find examples of single locks on the Stratford, Llangollen, Caldon and Oxford canals.

Broad locks are double the width of a single or narrow lock. They allow two narrowboats to go through together, or one widebeam boat on its own. Examples of canals with broad locks include the Kennet & Avon, Grand Union, Trent & Mersey and Leeds & Liverpool canals.

Originally used as a way to control the flow between different canal company’s water, the stop lock worked to completely break the flow of water. As most canals are now managed by the Canal & River Trust, boat can move freely so most stop locks have been removed. There are stop locks at Kings Norton on the Stratford Canal, the Somerset Coal Canal and Worcester Bar in Birmingham.

This type of lock mimicks the blade of a guillotine. The gate is raised and lowered letting boats through. There aren’t many guillotine locks on canals, but there are more examples on river navigations. There’s a guillotine lock on the Rochdale Canal at Todmorden and you can see the remains of the guillotine lock at Kings Norton Stop Lock on the Stratford Canal.

Created for steep gradients, staircase locks have numerous locks in a row and appear like stairs in the landscape. Staircases don’t have pounds (areas of water) in between each gate. The top gate of one lock will also be the bottom gate of the lock above. Bingley Five Rise locks on the Leeds & Liverpool Canal and Foxton Locks on the Grand Union Canal Leicester line are examples of a staircase lock.

Lock flights contain pounds of water between locks. The Hatton flight on the Grand Union Canal, the Tardebigge flight on the Worcester & Birmingham Canal and the Caen Hill flight on the Kennet & Avon Canal are examples of a long flights of locks. Some lock flights have staircase locks within them, for example Foxton Locks on the Grand Union Canal Leicester Line.