Even without needing man-made waterways, the continent is still divided. There’s at least one lake that sits right smack on the Continental Divide (Lake Isa, in Yellowstone), and drains both ways. Admittedly, the drains are a couple of tiny little cricks that you could just step right over, but they’re water.
Thank you, I didn’t think of the word in that context.
(too late to edit) Probably because the Swedish word världsdel has one specific meaning whereas region can mean several different things depending on the situation.
“Region” in English can mean very small areas, such as the region around a village, or large areas that cross continental boundaries, such as Latin America or the Middle East. And regions can be defined by various criteria, including biology, geology, climate and culture.