Current questions and answers regarding the map editor.

Good night, I currently have about 6,000 areas on my map, but I need to delete half of them, rework part of the map, and insert a smaller number of areas in other places. This raises the question: how can I quickly delete the created areas, other than clicking on each one in the editor and deleting them? Where are the created areas actually stored? Is there a file where I can quickly get rid of them? (I assume they are stored in the map itself and cannot be deleted any other way, right?)