This is an amazing apartment. It is about three minutes walk from the beautiful Old Town Square with its many tourist attractions. If you continue for another five minutes, you are in a quiet neighborhood, with few tourists, where you find a bakery, a market, and some smaller restaurants. A big shopping mall is a ahort walk away. Ten minutes gets you to the famous Charles Bridge (go VERY early to miss the crowds). We didn't have time to visit the castle and cathedral, but they would have been easy to reach.
The apartment was extremely comfortable for us, four adults in three bedrooms. It is on the first floor. There is a restaurant on the ground floor, and some noise from patrons who sit outside. We were prepared for that after reading airbnb reviews, and it was a small inconvenience when measured against the opportunity to experience life in the center of Prague.
If you are driving, be aware that the apartment is on a narrow pedestrian only street. For quick unloading, cars can go to about 50 feet from the building. There are parking garages nearby. It's not a good idea to try to drive in the city center.