There are huge swathes of unpopulated land across the world.
However in many areas the local zoning rules prevent you building on them.
In Australia for instance, thousands of acres of Rural land have been rezoned as "Farming", which means that you can't build a house on less than 100 acres. And of course the only ones who benefit are the corrupt real-estate developers.
https://www.youtube.com/c/BilliSpeaks/videos