Orthanc, Tower of Isengard was created in the second age by man kind. The tower is described to be made from the stones around Isengard, and formed into a single near indestructible tower with four distinct sides. It has horns that stick off the top and has tips that are as sharp as spears.

This is my interpretation of the tower based off of the popular Lord of the Rings trilogy by Peter Jackson. The tower is hollow on the inside so you can create your own minecraft base inside the tower. The tower is also very tall, reaching around 230 blocks high.