Crowds

That is correct. The reference is most like to the Charles bridge which is always packed with wall to wall people, vendors, etc. - think of a packed elevator car. In other parts of the old city it will be crowded and very crowded in August but not walking on your feet. This is a time you will want to have empty pockets and carry backpacks/day bags very carefully near your ankles.

The entire way from the main market square or Old Town Ring (where that clock is) to the Karl's bridge is like the line at the security checks at an airport - just with plenty of pick-pockets. I really love Prague and get to go there for business rather frequently. But I always avoid that part of town...

Peggy, I was in Prague last September and didn't find it crowded to the point that others were "walking on the back of my feet". It could certainly be busier in August though, as that's when a lot of Europeans take holidays. The Charles Bridge can be busy during the day, but it thins out at night. There were some good street musicians performing there, and it was nice to stop for a few minutes to listen to the music. The streets leading to the bridge on both ends are often more crowed as they're somewhat narrow, with sidewalk cafes jutting out. Prague does have a reputation for Pickpockets, but I didn't have any problems (thankfully). Be sure to wear a Money Belt though, and DON'T access it where anyone can see. On one end of the bridge, it's necessary to wait for a light to cross a small street, so pedestrians are "packed" fairly tightly at times. That's one spot where you'd need to be extra vigilant. Happy travels!