A longtang is a traditional type of residential lane and community located in Shanghai, China. The term refers specifically to the narrow lanes that houses face or to groups of interconnected houses organized around these pathways. It is considered the Shanghai equivalent of the hutong found in Beijing.
The area is sometimes referred to as a lilong, a name that incorporates the "-li" suffix commonly used for residential developments during the late 19th and early 20th centuries. These communities are characterized by their unique urban layout where multiple houses are connected by shared lanes or interconnected pathways.