| NYC's bus fleet is slower than San Francisco's, with some routes netting 2-3 MPH. Note that urban traffic speeds, net of stops, are often quite modest, and that "dwell times" and stop frequency have a profound impact. Even BART, with its 80 MPH peak speeds, averages about 35 MPH for longer throughway routes. You can verify this roughly by comparing BART travel times with driving distances in Google Maps. But cities with slow average transit speeds are also generally pretty dense. Remember, SF is 7 miles square, do even 8.1 MPH gets you from one end to the other in an hour (and that's pretty much a worst case). Google Maps shows the SF Ferry Building to SF State (a cross-town trip) as 21 minutes by car (good luck with parking), or 39 minutes by transit. Worse are trips between less-travelled areas. The Marina to SF Zoo is a 21 minute drive, but 1h2m by bus. Driving from the Ferry Building to the de Young Museum in Golden Gate park is only 5.8 miles but would take 21 minutes -- that's 16.5 MPH, by car. Access to highways vs. surface streets makes a big difference. |