It's a strange kind of heat too, even without the sun beating down on you, the air is so hot and thick, it's like wearing a blanket while breathing soup.
However, in Eastern Europe most people installed split AC units in their apartments to counter this but in Western Europe that's not allowed in apartments so if you're at home or working ouside, instead of an air conditioned office, you're gonna cook.
Later EDIT: To clarify, you ARE allowed to have AC but due to regulations it's very difficult to get permission for city apartments as it has to be a centralized unit for the whole building with planning to certify that it won't affect the aesthetic of the building or be too loud or hot for the neighbors. If you want a split unit just for your apartment you'll never get permission, so basically, you're not allowed to have one. In EE regulations are lax or don't exist or are not enforced so everyone and their mums has AC.