The Singapore River is approximately three kilometers long from its source at Kim Seng Bridge to where it empties into Marina Bay and finally the Singapore Strait; the river extends more than two kilometers beyond its original source at Kim Seng Bridge as Alexandra Canal, as far as the junction of Commonwealth Avenue. Here there is a break with Buona Vista Road where Sungei Ulu Pandan starts and flows into Sungei Pandan which in turn flows into the sea at West Coast Park. Thus, the source of both these waterways is in the Queenstown, Ridout Road Estate and Tanglin Halt area near Margaret Drive.