Two facts that I've long struggled to reconcile are that The Lord of the Rings is supposed to be a story about and for England, and yet it's very clearly set on a continental mainland.
I've finally figured out how to fit these facts together neatly, though: the Third Age ended before Doggerland sank. Britain was not an island until at least some time into the Fourth Age.
This would also explain where the Orcs went; the elves all sailed off to Numenor, and the Orcs had their homelands, such as Mordor, become the seabed of the North Sea.












