For his/her tour in Prague, each visitor can choose the places that he/she likes the most, and, thus, the tour, in Prague, can be "tailor-made" for everybody.
The duration of the tour depends, of course, on interest and also on the time available for visitors. A quick tour takes 3-4 hours. A calmer and more detailed visit can take twice the time. Normally and in order not to tire the visitors too much, it is recommended to make a visit to Prague in 2 days - on the 1st day, a portion (3-4 hours) of the tour and, on the next day, the 2nd part of the tour.