history 136 architecture 88 botany 65 physiology 57 agriculture 52 water courses 47 geodesy 36 more ... flóra 27 civil engineering 27 water courses regulation 25 air force 24 systematic botany 23 channels 22 railway transport 22 towns 21 dwelling houses 21 military aircrafts 21 geology 20 osobnosti 20 hydrology 19 water management 19 hydraulic structures 18 ancient monuments 18 geography 17 industry 17 inland water traffic 16 architectural designs 15 deposits mining 15 museums 15 water structures 15 less ...