Hey Gabriela! Actually, if you didn´t stop by, I would tag you in this post because I thought you would like this place and might want to include it in your itinerary :)

These quarries (there are actually more of them in this area) are easily accessible on foot from the Karlstejn Castle, which is just a short (30 minutes) train ride from Prague so you can definitely make it ;) The path around the crater is safe, well marked and well maintained so even your "non hiking" friends will make it ;)

No worries, haha, we are a small country but with a lot to offer :) I have spent most of my life in the Czech Republic but there are still so many cool places here that I haven´t visited yet so don´t be afraid of missing some :) Even if you pack your itinerary as much as possible, you will see just a tiny fraction of what the country offers but it´s ok and it will make you want to come back ;) You will enjoy your time here, I´m 100% sure...