It's a bosmer town.
First, take a look at the picture: http://elderscrollsonline.com/en/media/concept-art/309
Notice anything off? How about the wooden buildings? The most unique thing about the bosmer is their reverse-veganism. They can't eat or use plant matter. They smoke grubs out of bone pipes, they eat their dead, they refuse to cut down any of their own wood. They drink fermented pig's milk instead of beer for goodness sake! It's why their society is so awesomely primitive in a lot of ways, and why they rely on stronger empires for resources and protection.
Did Zenimax just forget this?
It says that this city was the capitol of Valenwood under the aldmeri dominion. Did the altmer just donate their own wood? Why even do that if the bosmer already have architectural methods of their own? Maybe there is a way to rationalize it, but do you guys think this a sign of zenimax not paying attention to lore? Or is this just an INTENDED exception and valenwood at large will stay true to the lore?