There are a couple of places in the Netherlands with congested bike lanes, which is a great problem to have. It's crazy to imagine all those people in individual cars; we'd have reached congestion so much sooner. (Note that this is after decades of continuously improving bicycle infrastructure; basically everywhere else won't run into this problem any time soon.)
The problem isn't so much density (I think NYC is much denser), as much as it is the existence of really popular destinations; you'll see this close to some big train stations in rush hour, for example. Solutions are smarter road layout, and providing more and more attractive alternative routes, and alternative destinations (e.g. more train stations nearby).
The problem isn't so much density (I think NYC is much denser), as much as it is the existence of really popular destinations; you'll see this close to some big train stations in rush hour, for example. Solutions are smarter road layout, and providing more and more attractive alternative routes, and alternative destinations (e.g. more train stations nearby).