Región cárstica
A belt across the island's north made of eroded limestone, with rounded hills called mogotes, sinkholes and caves. It is the landscape that appears suddenly as you drive toward Arecibo and Camuy. Underground rivers run below that rock, and they carve the cave systems people visit.
Example
Those green egg shaped hills you see from the northern highway are mogotes, not ordinary hills.
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Related terms
Nature
Cavernas del Río Camuy
A cave system carved by one of the largest underground rivers in the hemisphere, in the island's north. The public...
Nature
Cueva Ventana
A cave near Arecibo whose mouth opens like a window over the Río Grande de Arecibo valley. The visit is guided, with...
History
Observatorio de Arecibo
A radio telescope built in 1963 inside a natural karst sinkhole near Arecibo, for decades the largest single dish in...
Nature
El Yunque
The tropical rainforest in the island's northeast, managed by the federal Forest Service and the only tropical forest...
Frequently asked questions
Why does karst matter to a visitor?
Because it explains the caves, the underground rivers and the shape of the north. Most adventure trips in that area come from this geology.
Where is it most visible?
Between Arecibo, Camuy, Utuado and Lares, driving secondary roads rather than the highway.
