yup, for instance Beijing (at in past not so many years ago) had extremely crowded subway that you have easily wait for 3-4 trains before you get on train and t

yup, for instance Beijing (at in past not so many years ago) had extremely crowded subway that you have easily wait for 3-4 trains before you get on train and that didn't really mean it's that popular, it just meant that population per subway line was much higher than elsewhere in Europe, it used to be something like 0.5M pop. per subway line in west, while Beijing had 1M/line, after recent expansion I guess it improved a bit, but you would really need paralel lines since some areas are extremely densely populated I mean it's popular of course (since there is really no alternative), but it doesn't mean it's good.