50 min from Prague by train from Main station (When on the Karlštejn Station turn right, cross the Berounka River, turn right again and after 50 meters turn left. Then follow the main road up to the castle.) Or if you like cycling there´s also very beautiful bike route along the river, it´s not hilly so it´s very easy - and if you don´t want to cycle on the way back you can hop on the train also with your bike.