Although rows of densely packed Victorian terraces with ginnels, snickets, wynds or alleys - depending on where you are - running between and behind are often referred to as back-to-backs, true back-to-back terraces share side and back walls.This means that, unless you are on a corner, the front door and windows are the only source of light and access. Most have been demolished due to substandard construction and poor ventilation and sanitation, but in West Yorkshire a few survive and are still occupied. This is back-to-back housing in Beeston near Leeds (2021). (The National Trust also owns these back-to-backs in Birmingham.)