The closest spring to town is Ain al-Arais, a cool, inviting waterhole with a grotto-like bottom, just five minutes' walk from the central market.

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The estate includes an 11, 500-square foot mansion, a two-bedroom guest house, a 2, 500-square-foot gym with boxing ring, a pool with a grotto, and a putting green.

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The grounds feature a detached guesthouse with a recording studio, swimming pool with a water slide, grotto and barbecue area.

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After negotiating their way down a series of steps carved into the steep rock face, explorers of the Blue Lake Grotto are faced with a deceptively deep pool of limpid blue-green water.

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Eleven different pumps recirculate water through the mountain, which includes a grotto area with a television, couch and bar.

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It links the Ice Palace, a grotto of ice sculptures, with the Sphinx Hall observatory.

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Its highlight is the Blue Grotto, a coastal cave filled with blue light.

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