Due to its position on the Mid-Atlantic ridge, Iceland is one of the most active volcanic regions in the world. Its unique geological conditions make for some awe-inspiring rock formations, both beneath the surface as well as above it. Various tube caves—formed by magma flowing underneath the earth's surface after lava has solidified overhead—can safely be explored through guided excursions year-round.
For safety reasons, different caves are explored during different seasons. The most commonly visited caves are the Gjábakkahellir Cave near Þingvellir National Park in the summer months, and the Leiðarendi Cave in the Bláfjöll area in wintertime.
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