skid row; underworld; haunt of vice
A somewhat literary or figurative expression for a place where criminals, vice, or social outcasts gather. Often used in descriptions of dangerous or seedy areas.
That district was once called a haunt of vice.
Compound of 悪 (aku, 'evil') + の (no, possessive particle) + 巷 (chimata, 'crossroads, public place'). The exact historical derivation is uncertain, but it is a set phrase meaning a place where evil or vice gathers.