Happy birthday Mammoth Cave National Park! The park, which is home to the world's longest-known cave system, became a national park on this day in 1941. ⁠ •⁠ •⁠ 📸 by @tyler.groom⁠ •⁠ •⁠ Remember to use #nationalparkspartnership in your captions for your chance to be feature on this page! ⁠ •⁠ •⁠ #kentucky #cave #nps #nationalpark #nationalparks #kentuckycaves #caving #findyourpark #nationalparkphotography #mammothcave #mammothcavenps #kentuckyproud #explorekentucky #roamkentucky