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As you crest the lip of the crater you see that the lining of the cone is unusually smooth. You peer down towards the vent at its centre and your suspicions are further aroused when you note that this hole is perfectly symmetrical. No natural volcanic forces could have created this precisely circular vent and it prompts you to take a closer look. When you reach the base of the cone you discover a circular platform of carved stone blocks constructed around a well-like opening. When you look down into this well you are half-expecting to see smoke, or perhaps the glow of molten lava, but to your surprise you discover it is filled with a shimmering blue light.