Hildórien

After the Awakening of Men, Hildórien is not subsequently mentioned, and it may be that it was lost in the mists of time, like the Elves' place of awakening at Cuiviénen. On the other hand, Men awoke much more recently than the Elves, and unlike Cuiviénen, Hildórien is never explicitly said to have been lost. At least in principle, then, it's possible that the ancestral lands of Men were still inhabited by them until the time of the War of the Ring and even beyond.

Hildórien is only shown on one very early sketch map, reproduced in volume IV of The History of Middle-earth. Though this map has little in common with later versions, the conception of Hildóien as lying on the far eastern edge of Middle-earth was clearly retained.

Incidentally, the region labelled 'Mid-land' was so named to indicate that it lay in the central parts of Middle-earth, between 'Northland' and 'Southland'. Though these specific names aren't seen in later works, the terms 'Northlands' and 'Southlands' did survive as general terms for broad areas of Middle-earth.