Adoquín azul
A block of iron slag with a bluish sheen that has paved the streets of Old San Juan since the late nineteenth century. It arrived by ship from Europe, where its weight served as ballast in the holds before being unloaded at the port. It is beautiful and slippery in the rain, so footwear matters more than you would think.
Example
After a downpour the cobbled slopes of Old San Juan get genuinely slick and smooth soles show it.
Best tours and tickets
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Cave, Waterfall and River Adventure in Charco Azul from San Juan
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San Juan Guided Turtle Snorkel Tour and Complimentary Videos
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Top Rated El Yunque Rainforest & Waterslide - SmallGroup Tour
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Frequently asked questions
Why are they blue?
Because they are not natural stone but iron furnace slag, and that material carries a bluish tone that deepens in rain.
Can I wear heels?
A bad idea. The joints are wide and the surface uneven, so flat shoes with grip win.
