the 1960s emigrated primarily from Turkey. Among them is the former cloister from the abbey church of St. Peter and Paul. The historical city hall in Obermarsberg originates from the 13th century and was refurbished after the Thirty Years' War. There are different theories about the reasons for leaving the place. Golden Gate Park, which is over four kilometers in length, offers a botanical garden, planetarium, Japanese garden and an aquarium. It serves as a local place of rest and relaxation for San Franciscans. The Yerba Buena Garden was built at the beginning of the 1990s on the roof of the Moscone North Convention Center. It contains a monument to Martin Luther King, Jr. Since the 1960s, the city's economy has been in steep decline. During the 2010