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30. Pennsylvania - This northeastern state may not be in the top 20 as a tourist destination, but it has plenty to offer. If you're a history buff, make sure to visit the Liberty Bell in Philadelphia or the Civil War battlefield in Gettysburg.

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29. Minnesota - Other than being considered the happiest state in America, Minnesota is home to plenty of green places, such as the town of Grand Marais on the shore of Lake Superior.

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28. Indiana - If a picturesque hike is what you're after, then look no further than Hoosier National Forest.

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27. Washington - Take a dip under one of the many waterfalls in North Cascades National Park, and be sure to check out Columbia River Gorge while you're at it.

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26. Maryland - Lose yourself in American history at the star-shaped Fort McHenry and the Antietam National Battlefield from the Civil War.

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25. Mississippi - Indulge in the old-school Mississippi Delta music scene at Elvis Presley's birthplace or the Delta Blues Museum.

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24. Oregon - If you want to experience a real-life volcano then go to Mount Hood and Crater Lake. Don't forget to drive by the extraordinary Multnomah Falls.

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23. Louisiana - Treat yourself to stunning French colonial architecture at Jackson Square and, of course, the St. Louis Cathedral in New Orleans.

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22. Missouri - No trip to Missouri would be complete without a day spent fishing and basking in the beauty of the Lake of the Ozarks.

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21. Michigan - Get off the beaten path and take a boat ride to the breathtaking islands of Isle Royale National Park in Lake Superior.

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20. Iowa - Despite what you may believe, Iowa isn't just a long string of cornfields and open space. You are in for a real adventure at Maquoketa Caves State Park.

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19. Kentucky - If a horseback ride over wide-open plains isn't your scene then check out the magnificent sandstone arches at Red River Gorge.

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18. Alaska - Get lost in the abundant wildlife and spectacular views of the Denali and Kenai Fjords National Park, or one of Alaska's many other protected forests.

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17. Wyoming - A trip to Wyoming automatically includes a mandatory visit to Yellowstone National Park and the monstrous geyser, Old Faithful.

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16. South Dakota - South Dakota isn't just Mount Rushmore, if you're up for an unforgettable experience trekking through the rugged natural formations and wildlife in the Black Hills and Badlands National Park.

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15. New Mexico - Explore the 11,000-year-old ruins of Pueblo civilizations at the Bandelier National Monument, and indulge in the wealth of indigenous art in Santa Fe.

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14. Delaware - Live the charmed life for a day and check out the historic estates at Nemours Mansion and Gardens.

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13. Idaho - How many people can actually say that they have camped out in a dormant volcano? Pitch a tent and gaze at the stars in the Craters of the Moon National Monument and Preserve.

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12. Montana - Get out in nature and hike one of the 700+ mi of trails to see the world's greatest collection of geysers at Glacier National Park.

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11. Oklahoma - Check out a real Western-themed amusement park at Frontier City and learn about the American West at the National Cowboy & Western Heritage Museum.

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10. Connecticut - Travel back in time at the Medieval mansion in the Gillette Castle State Park.

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9. North Dakota - Stop by Theodore Roosevelt National Park to see where the Great Plains meet the Badlands, and wild bison roam free.

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8. Maine - Come to Acadia National Park—in Maine's Mount Desert Island—and experience glacier peaks while spending an afternoon whale-watching.

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7. Arkansas - Who needs a resort spa when you can take a dip in historic 20th-century bathhouses at Hot Spring National Park?

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6. Kansas - Stop and smell the flowers—literally—at Botanica, The Wichita Gardens and treat yourself to a fairy tale afternoon surrounded by wildflowers and butterflies.

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5. Rhode Island - Live life as an 18th-century aristocrat at the Vanderbilt mansion in Newport, or go see the Gilded Age-style Marble House mansion.

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4. New Hampshire - Come and enjoy stunning views and historic sites with over 800,000 acres of preserved forests at the White Mountain National Forest.

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3. Nebraska - Visit the Chimney Rock National Historic Site and see the famous 300-foot-tall rock formation towering over the North Platte River valley.

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2. Vermont - Get ready for a day of outdoor adventures at Lake Champlain with sailing, fishing, boating, and cycling.

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1. West Virginia - Travel through America's past at the Cass Scenic Railroad State Park, or take an underground tour through the Phillips-Sprague Mine.

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