@ebel most use licence exempt ISM frequencies (as does #wifi) and techniques like #LORA with encryption - the range will depend on the types of antennas used/permitted power and that varies to an extent within countries, although some bands are common across the EU. In UK Ofcom's IR2030 document explains these (along with some UK specific allocations, Comreg, BNetzA and other similar agencies all have their own documents for each country)
@ebel be aware too that directly following some USA designed setups for mesh networks could lead to trouble as you can end up transmitting on frequencies still allocated to defence ministries (including military aviation comms!) in many countries, or worse, too strong a wideband signal in the wrong bit of the 433 and 868 MHz ISM band can lock everyone out of their cars, set off burglar alarms etc which isn't exactly "stealth" (and gets people calling the authorities out of frustration)
@vfrmedia OK, interesting... I dunno much about RF stuff. Maybe I should play.