![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/3/36/Flash_lock_drawing.jpg/640px-Flash_lock_drawing.jpg&w=640&q=50)
Flash lock
Gate in the flow of a river which could be opened to allow boats through / From Wikipedia, the free encyclopedia
A flash lock is a type of lock for river or canal transport.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/3/36/Flash_lock_drawing.jpg/640px-Flash_lock_drawing.jpg)
Early locks were designed with a single gate, known as a flash lock or staunch lock. The earliest European references to what were clearly flash locks were in Roman times.[3]