A strath is used to describe a large valley that is wide and shallow. In those days, Alexandra Canal (or Boh Beh Kang) was an never ending stream which passed through Hong Lim and Hong Yim Hills in Margaret Drive and Mei Ling. Farms were scattered along the banks of Boh Beh Kang and villagers in Margaret Drive made use of water from the stream for their livelihood. And this area was just like a shallow valley. Hence, it was called a Strath.