Hackney Brook is a tributary of the Lea that once flowed from Stoke Newington and through Hackney to meet the Lea near Hackney Wick. The Brook ran through what is now Clissold Park, Abney Park Cemetery, Stoke Newington Common and the western edge of Hackney Dowsn. It travelled across Mare Street, through Homerton to Hackney Wick and into the Lea near Wick Lane.
By 1856, much of the Brook had been culverted and diverted into the main sewer network at Old Ford.
The only surface evidence of the original course is the two ornamental lakes at the northern boundary of Clissold Park.