Either because of the visual representation from The Wizard of Oz or the fact it lies in the Great Plains, many assume Kansas is the flattest state in the United States. After thinking about the state's topographical reputation, a professor and graduate student at the University of Kansas conducted a study of flatness across the contiguous United States. While people might think of flatness in many different ways, Jerry Dobson and Joshua Campbell used geographical data to determine the percentage of flatness across each state. The three flattest U.S. states, according to this rigorous, peer-reviewed study, are as follows.

North Dakota

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As one of the least populous states in the United States, and the flattest, some might not automatically think of North Dakota as a vacation destination. But North Dakota residents and other fellow Midwesterners know that North Dakota offers a distinctive culture and breathtaking landscapes. Once having a strong Native American presence, the state is home to historical sites and small museums dedicated to specific people and events, such as Fort Buford and Fort Union Trading Post. You can also travel along the Enchanted Highway, which has one of the best roadside attractions in the United States. Here are some other fabulous locations for fun times in North Dakota:

Fargo - Fargo is North Dakota's largest city, even if it's small when compared to other large cities in the Midwest. This city is North Dakota's hub for arts and culture. The city has several museums, including the Fargo Air Museum, The Plains Art Museum, and Bonanzaville, a historic area of the city where you will find artifacts and Fargo's first house.

Theodore Roosevelt National Park - Established by President Truman in 1947, Theodore Roosevelt National Park is a paradise for those who love to hike, camp, and connect with the outdoors. The least flat part of North Dakota, the park offers 100 miles of trails and ample opportunity to view the region's distinct wildlife. Also, you can see several historical sites with background information on Teddy Roosevelt's time there in the late 19th century.

Devils Lake - This 160,000-acre lake is North Dakota's largest body of water. The lake area draws outdoor enthusiasts all year long for fishing, ice fishing, water sports, and more. The lake gets its name from the Native American lore, which tells of bad spirits in the water.

National Buffalo Museum - The National Buffalo Museum in Jamestown, North Dakota, has lots of art and exhibits. It's dedicated to educating the public and honoring the North American bison who live in the region.

Illinois

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While a good portion of rural Illinois consists of expansive agricultural fields, this flat state in the Midwest is home to one of the largest urban centers in the world. One of Illinois's greatest assets is the juxtaposition of Chicago's hustle and bustle with the more serene locations and activities found in Central and Southern Illinois.

Whether you find yourself in Chicago for the first or the 50th time, these are three locations you have to visit at least once in your life:

Navy Pier - This Chicago landmark allows visitors to participate in fun events and cultural activities with the panoramic backdrop of stunning Lake Michigan. Families will enjoy the rides and the Chicago Children's Museum. All visitors can try out multiple dining options and enjoy live music and shows.

Millennium Park - Located in downtown Chicago, Millennium Park is home to Cloud Gate. This famous art installation looks like a big silver bean. The park has several fountains, a rock climbing wall, multiple dining options, and a pavilion for live entertainment.

Art Institute of Chicago - Art lovers cannot miss a trip to the Art Institute of Chicago located next to Millennium Park. Here, you can see famous paintings such as American Gothic by Grant Wood and Water Lilies by Claude Monet.

Don't underestimate the rest of Illinois, where you can enjoy many different highlights, such as:

Illinois Route 66 Hall of Fame & Museum - Road-trippers looking to "get their kicks on Route 66" can soak up the history at the Route 66 Hall of Fame and Museum in Pontiac, Illinois. The museum offers thousands of pieces of memorabilia associated with the historic route and its importance throughout the country.

Starved Rock State Park - After visiting Starved Rock State Park, you might doubt Illinois is a flat state. Starved Rock State Park has 18 canyons along the Illinois River and 13 trails giving access to stunning waterfalls.

Springfield - Illinois's capital city is home to the Lincoln Tomb and the Abraham Lincoln Presidential Library and Museum. Although he was born in Kentucky, Lincoln spent many years in Springfield prior to his presidency. Visitors will find numerous historical landmarks and can also visit the Illinois State Museum.

Florida

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With Disney World, Universal Studios, and other theme parks, Orlando, Florida, is the theme park capital of the world. Also, Florida has much more to offer than just theme parks. When you get out of the Orlando area, you can find incredible beaches, rich history, and engaging cultural activities. Florida is also home to several beautiful golf courses. It's difficult to include all of the great activities and places in Florida, but the following list includes some of the most exciting destinations throughout the state:

St. Augustine - Nestled along the northeast Atlantic Coast of Florida, St. Augustine is the oldest city in the United States. It's famous for its Spanish colonial architecture. St. Augustine is close to some of the area's most picturesque beaches and home to several historical sites, such as their lighthouse and the Castillo de San Marcos.

Cape Canaveral - Home to Kennedy Space Center, Cape Canaveral is the perfect trip if you're interested in NASA operations or want to see a rocket launch.

Miami - As Florida's cosmopolitan center, Miami offers world-class dining, museums, and the art deco glory of South Beach. Visitors enjoy the mixture of cultural influences from Cuba, the Bahamas, and Caribbean nations in Miami's food, music, and architecture.

Sanibel Island - This favorite Florida getaway location offers a relaxed atmosphere for couples and families. Take a bike ride across the island and enjoy one of the best opportunities for gathering seashells in the United States.