Yeşil Türbe
The Green Tomb, built in 1421, is the final resting place of Mehmet I Çelebi. It's actually covered in blue tiles, added after an earthquake damaged the originals in the 1800s, but inside are incredible original İznik tiles, including those—many of which are green and turquoise—sheathing Mehmet's immense sarcophagus. The surrounding tombs belong to Mehmet's children.