The Stone Forest (Pobitite Kamani in Bulgarian, meaning 'stones hammered into the ground') is an area of odd rocky features about 10 miles west of Varna. It is actually several groups of stones covering a couple of square miles. Regarded as the most unusual natural phenomenon in Bulgaria, each group contains hundreds of natural pillars, with some reaching 20 feet and more into the air. Varying in shape, some resemble animals, while others look like calcified fountains. All look like someone deliberately placed them in the surrounding sand, hence their name. Often referred to as a 'petrified forest', experts aren't completely certain of their precise origin, although it is known the stacks formed on the seabed around 50 million years ago. It is thought they were left high and dry when the waters receded and the softer rock around them eroded away. Opinions also differ on the charms of this place. Some find it to be a mystical experience; others only see a pile of old rocks. Perhaps the main attraction for many is the very fact that their origins have yet to be fully explained.