When my city gets large enough to get crematoriums and incinerators, I generally use those over cemeteries and landfills. They don't need to be emptied, and I'm going to need the burners anyway to empty the other buildings. Invariably, my city winds up with dead bodies (and trash) in almost every building, so that got me wondering if I do need cemeteries to perform the initial body pickup? And crematoriums are only used when emptying cemeteries? Or do crematoriums actually collect dead bodies from buildings, and my large number of uncollected bodies is indicative of another problem (traffic?)?
Must I have cemeteries / landfills or can I use crematoriums / incinerators exclusively?
Yes, you need both cemeteries and crematoriums, as some citizens will refuse to be cremated. (Source : Cities Skylines guide)
For trash this is not necessary, you can suffice with just incinerators as trash doesn't really have an opinion on how it is disposed off.
For both it is important to build enough facilities spread out trough the city as they have a limited number of trucks/hearses and these need to drive trough traffic to the pick up location.
some citizens refuse to be crematedSee, this is why we need to expell all the elderly from the city. They don't work, they don't pay taxes, and all they do is complain about how they want to be cremated inefficiently. May 18, 2018 at 0:40
2That is nonsense as far as I know. crematoriums simply do not have enough hearses to keep the ovens running constantly. Cims in cemeteries do need to be cremated eventually, too. That said, it is helpful to have a mix - use cemeteries to stockpile the dead while the crematoriums are turned off - and then empty the cemeteries into them when the storage is full.– ChieronMay 5, 2019 at 1:28
NO, If you have placed your cemeteries / landfills close to the highway where they have fast access to any part of your city, YOU NEED NOT use land-based facilities. Cemeteries or landfills are no longer needed as long as you have setup these facilities in the best places.