I’m not sure why, but monasteries attract me so much. So, I quite often visit some around Sofia and in province. And that is not so hard. Around Sofia, near to go for one day and with public transport have 38 monasteries. Half of them are famous as group – Sofia Holy mount Minor – as monasteries in Mount Athos, but not so impressive.
And in Sofia Province things are better – about 100 monasteries and more 30 medieval churches and ruins.
Here a blog logs about walk to Monasteries in Nishava river, west from Sofia