Ecologically diverse and sparsely populated, the Big Island of Hawaii is larger than all the other better-known Hawaiian islands combined. Rental cars allow visitors to discover wonders from snow-capped mountains to rainforests to deserts. Best known for Hawaii Volcanoes National Park, home to the longest volcanic eruption in recorded history, the Big Island caters both to those who crave adventure and to those looking for luxury, with the flotilla of decadent mega-resorts dotted along Kohala Coast.