I recently visited the Potter Park Zoo in Lansing, which is a fairly small zoo with not a lot of turtles. They did have 2 Greek tortoises that I could see, chillin' in their enclosure. One of the tortoises has some pyramiding. I attached photos with greater resolution so you can zoom in on them. I can post more photos of them next time I visit, since I love to see the rhinos in warmer weather! 
