I was thinking this, too. I can't imagine anyone--even those from out of town--thinking that walking 3-4 blocks to a subway station in NYC is too far to handle

I was thinking this, too. I can't imagine anyone--even those from out of town--thinking that walking 3-4 blocks to a subway station in NYC is too far to handle. Re: another comment, the Paris Metro _is_ dense enough to work in the city proper - but only in the city proper. A side effect is that the service is super-slow except on 1-2 lines. The slow speed makes it nearly impossible to expand to the marginal/suburb areas, so you wind up with a similar situation to New York's outer boroughs.