Middle Earth Architecture

I dont know if this has been discused before but I had recently notices that Gondor and the Elves were the only civilizations that built towers, I believe that gondor builds towers because of the lineage to numenor, who were part elven, if im not mistaken. But you may say about Barad-Dur, I have through about this, and since sauron was under the service of melkor in the first age, and most of melkor's creations were made in mockery of other races (elves/orcs, trolls/ents etc.) so I believe that sauron, taking a page from Melkor, built Barad-Dur as a mockery of Minas Tirith and Minas Ithil. What do you nthink?