What's the source? I've used public transport in more than half of these cities and I would rate both Amsterdam and Vancouver above the lot (though I don't know the top three).
Hi CardinalSin, the source is kind of iffy because it’s hard to find an exact way to measure best transit. I considered going by % of the city covered but it would be unfair for larger cities that have urban sprawl (like Mumbai) vs small cities (like San Francisco). The source I ended up using was from various articles, mostly rated by citizens of the city or by transit enthusiasts. This list is very subjective, and a case could be made that any city has the best transit! I agree that Amsterdam and Vancouver also has great transit, but this list is just an opinion (as are many other things in life!). Thanks for your comment, CardinalSin! Have a great day! :D