I thought that it might be good to write down some basic information about how I organize my bike trips. Maybe someone will find it useful when organizing their trip.
I always start with choosing the route on mapy.cz which is my favourite website ever. The bike routes are marked with violet colour ( on tourist map) and there is plenty of them in Czech Republic and around Prague. As a starting point I usually choose a place which is well connected by train and the same applies to finish point ( unless I am coming back to Prague and catch metro). As I am usually biking alone, I try to choose the route in such a way that, if something happens, I can come back to Prague. This means that there needs to be train or bus line somewhere near.
Depending on the connection and the level of difficulty, I bike from 50 to 100km during one trip. I am more into long distances than to speed in general but also I like to know that there is something pretty to see on the way. Very often, I use the photographic version of the map to see which way is nicer and I adjust my rout accordingly. During summer I go further from Prague and I usually make a good research on which part of Czech Republic I should go to. I am a typical cyclotourist so I am not into MTB or any kind of adrenaline version of biking. However, I am fine with climbing some hills and forest paths and all this I can usually check when planning the route on the map. Mapy.cz also show you the inclinations of the chosen route which is very useful if you want to estimate how challenging will be the trip.