And look at Ebonheart x) Its not supposed to be there.But just a bit north.
But Thats a weird map.but its the first tamriel map
Not entirely.
There are two Ebonhearts. The one
before TES3:Morrowind (like the one on that TES:Arena map) was located on the southern shore of the Inland Sea, the one
after TES3:Morrowind was located on the northern shore of the Inland Sea. Reffered to (these days) as Old Ebonheart and Ebonheart respectively.
Even the map you linked to yourself shows both.

So each of the Hold cities is about 10 times bigger than what we get to see but because the engine is limited you ether make huge cities but small landscapes or have everything equal in scale.
It's not because of engine limitations. It's a design choice. A game on that scale would be a huge task, especially filling that huge world space with locations, people, life.