"Cueva Ventana is a cave atop a limestone cliff in the mountainous town of Arecibo about an hour from San Juan . Its name translates to “cave window.” One hikes up and looks through for a gorgeous view of mountains and river. Head over on a weekday, when non-resident tickets are $19 for a 90-minute guided tour. Although the cave isn't recommended for anyone with mobility issues, adventurous travelers who aren't afraid of heights will love it." - Alicia Kennedy
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