This adventurous tour is your chance to go cave exploring and snorkeling in one incredible day. On this day trip from Reykjavik, visit Iceland's Gjábakkahellir cave and the Silfra fissure, both located in the UNESCO World Heritage-listed Þingvellir National Park. Marvel at unique sights and discover the depths of some of Iceland's most stunning natural wonders as you explore a mysterious cave and snorkel in a pristine, dream-like underground pool. Your friendly, knowledgeable guide will make sure that you have an unforgettable experience.