Yosemite National, California https://m.flickr.com/
Beelitzer heilatten walkway in Germany :)
Arenal Volcano National Park, Costa Rica
Devetaki cave, Bulgaria
Madain Saleh is an old city in Saudi-Arabia. It is a sister city of Petra, built by the Nabateans more than 2000 years ago. It is located about 400 kilometres to the north-west of Medina and 500 kilometres to the south of Petra.