Now, you know that feeling when you’re so excited that your bladder suddenly goes too full? If you’re here in the subway, it might prove tricky, because there are generally no bathrooms around. Why’s that? 

Or how, for that matter, can you even breathe so deep underground? Why is it warm in the subway in winter and cool in summer? Why do escalator handrails move faster than the stairs? There are so many questions about the subway waiting to be answered, so off we go! Learn more about your ad choices. Visit megaphone.fm/adchoices