The document provides a history and timeline of the cable cars in San Francisco:
- Andrew Hallidie tested the first cable car system in 1873 which led other lines to convert from animal power to cable cars.
- By 1912, only 8 cable car lines remained but buses started replacing them in the 1940s as the mayor sought to close the system.
- In 1947, citizen Friedel Klussmann rallied to save the cable cars through a petition that forced the city to maintain the iconic Powell Street line.