and the subway was served only on weekdays until 1982. The K Ingleside line began using the entire Metro subway on weekdays on June 11, 1980, the L Taraval and M Ocean View lines on December 17, 1980, and lastly the J Church line on June 17, 1981. Meanwhile, weekend service on all five lines (J, K, L, M, N) continued to use PCC cars operating on the surface of Market Street through to the Transbay Terminal, and the Muni Metro was closed on weekends. At the end of the service day September 19, 1982, streetcar operations on the surface of Market Street were discontinued entirely, the remaining PCC cars taken out of service, and weekend service on the five light rail lines was temporarily converted to buses. Finally, on November 20, 1982, the Muni Metro subway began operating seven days a week. At the time, there were no firm plans to revive any service on the surface of Market Street or return PCCs to regular running. However, tracks were rehabilitated for the 1983 Historic Trolley Festival, and the inauguration of the F line, served by heritage streetcars, followed in 1995. By the late 1980s, Muni scheduled 20 trains per hour (TPH) through the Market Street subway at peak periods, with all trains using the crossover west of Embarcadero station to reverse direction. To allow for high frequencies on the surface branches, eastbound trains were combined at West Portal and Duboce Portal, and westbound trains split at those locations. Two-car N Judah trains and one-car J Church trains (each 10TPH) combined at the Duboce Portal, while two-car L Taraval trains (10TPH) alternately combined with two-car M Ocean View and K Ingleside (each 5 TPH) trains at West Portal to form four-car trains. However, this provided suboptimal service; many inbound trains did not arrive at the portals in time to combine into longer trains. Muni meltdown In the mid- to late-1990s, San Francisco grew more prosperous and its population expanded with the advent of the dot-com boom, and the Metro system began to feel the strain of increased commuter demand. Muni criticism had been something of a feature of life in San Francisco, and not without reason. The Boeing trains were sub-par and grew crowded quickly. And the difficulty in running a hybrid streetcar and light rail system, with five lines merging into one, led to scheduling problems on the main