Illinois

In 1900, Chicago made a river flow backward. The city had been dumping sewage into the Chicago River, which emptied into Lake Michigan, the same lake people drank from. Thousands were dying from cholera and typhoid.

So engineers dug a 28-mile canal and reversed the river's flow, sending the water toward the Mississippi instead. St. Louis sued. The Supreme Court sided with Chicago.

Long before any Europeans arrived, the Illini, Potawatomi, Kickapoo, and other Native peoples lived across this region for thousands of years. In southern Illinois, a city called Cahokia had roughly 20,000 people around the year 1100. That made it bigger than London at the time.

French explorers showed up in the 1670s, and the British took over after the French and Indian War. Illinois became the 21st state in 1818.

A young man named Abraham Lincoln moved to Illinois in 1830 and never left. He practiced law in Springfield, debated Stephen Douglas on slavery across seven Illinois towns in 1858, and won the presidency two years later.

In 1865, Illinois became the first state to ratify the 13th Amendment, which abolished slavery.

Then came the fire. On October 8, 1871, the Great Chicago Fire destroyed 18,000 buildings, killed about 300 people, and left 100,000 homeless. Chicago rebuilt so fast that by 1885, it had invented the skyscraper. By 1893, it was hosting the World's Fair.

You can visit Lincoln's home and tomb in Springfield, both preserved as national historic sites. In Chicago, take an architecture boat tour down the river they reversed and see the skyline that rose from the ashes.

Walk through the Field Museum to see SUE, the largest T. rex ever found. Grab a Chicago-style deep dish at Lou Malnati's or a loaded Italian beef at Portillo's. And at Cahokia Mounds in Collinsville, climb a 100-foot ancient pyramid that was thriving here 400 years before Columbus showed up.