He points out that both Hong Kong and Zurich have managed to make a success of their rail systems, heavy and light respectively, though there are few cities in the world as hilly.

他指出，尽管世界上很少有城市像香港和苏黎世那样多山，但香港和苏黎世都成功地建设了各自的轻铁和重铁系统。