The present invention provides a utility line extension and retraction system for enabling users thereof to selectively extend a utility line for utility line use and retract the utility line for utility line storage. The utility line extension and retraction system essentially comprises a plurality of utility line cassettes. Each utility line cassette essentially comprises two laterally-spaced, pulley-receiving walls, an anterior line outlet end, a posterior line inlet end, a stationary pulley assembly adjacent the anterior line outlet end; a traveling pulley assembly intermediate the anterior line outlet end and the posterior line inlet end, and a utility line extending from the posterior line inlet end to the anterior line outlet end, which line imparts motion to the traveling pulley assembly. The traveling pulley assembly travels along a closed path comprising an ascension path, a descension path, and an extended-state rest stop intermediate the ascension and descension paths.