Lava Beds National Monument is located near the city of Tulelake, California in Siskiyou & Modoc Counties.  It lies at the northern flank of the Medicine Lake Caldera to the south.  It was established in 1925 & houses a variety of volcanic features, faults, caves, history, & archaological sites.Much of the northern part of the monument contains history of prehistoric use of the area.  Pictographs & petroglyphs can be found inscribed on rocks at nearby cliffs and caves.  The Modoc War (1872-1873) was fought at Captain Jacks Stronghold, an effort for Modoc Indians to protect their territory from US army forces.The southern part is known for its caves, craters, and lava flows.  The Cave Loop is a popular area to explore several main caves in the park.  These caves are known as lava tubes & contain unique features such as lava shelves, lavacicles, skylights, cupolas, aa & pahoehoe floors, as well as narrow passages short enough one has to crawl through.  Make sure to have a flashlight, a hard hat, & knee pads when exploring.  Some caves even have ice formations & one cave, Mushpot Cave, has a lighted pathway & interactive signs.  The longest lava tube in California, Catacombs Cave, is located in the monument along the Cave Loop.The area is situated in a semi-arid environment w/ a juniper and sagebrush setting.  The wildlife is abundant w/ plenty of bird species in nearby Tule Lake National Wildlife Refuge to the north.  Views of Mt. Shasta to the southwest, the Warner Mountains to the east, & a good portion of the Klamath Basin & Southern Oregon to the north make this area a picturesque location.  One campground is located in the park near the visitor center, but is limited in spaces.Being relatively small in size compared to other parks in the USA, there is plenty to see above ground & underground.Source Wikipedia