Iowa's schools are pretty good, and they cover a whole lot of Iowa history. Chances are, you have heard the story of how Julien Dubuque founded the first settlement in Iowa with help from the King of Spain and neighboring Natives, and you might be familiar with Iowan abolitionists bringing the Underground Railroad through the state to assist runaway slaves. Unfortunately, not all of Iowa history is full of happy endings - here are a few of the darker stories of our state's past that tend to get buried beneath the highlights. They are the things of which Iowa ghost stories are made.

1. The Flood of Rockdale

The town of Rockdale, near Dubuque, was once a bustling mill town. All of that changed on July 4th, 1876. The day was full of joy as the nation celebrated its 100th anniversary, and at around 10 p.m., it began to rain. It quickly turned to a deluge, and the Catfish Creek Mill Dam was broken by the rush of water. A 20-foot deep water wall rushed the village, and only one house was left standing along with the Mill. Forty-two people died in the flood. Some survivors were found washed into the treetops. The village was never the same, as most of its residents died, and it's now a ghost town.

2. The Gitchie Manitou Murders

In November 1973, five young teenagers went on a hike through the Gitchie Manitou Preserve. The group was attacked by three brothers, and four of them were killed. One young girl managed to escape after being raped and held captive. Her testimony brought the evil Fryer brothers to justice, but the region has never forgotten the horror of their crimes.

3. The Villisca Axe Murders

On the evening of June 9, 1912, six members of the Moore family and two of their children's friends went to bed in a peaceful southwestern Iowa town. By early morning, they would be found hacked to death by an unknown axe murderer. One suspect was tried twice and acquitted, and the mystery remains unsolved. The home where the murders occurred is said to be one of the most haunted places in Iowa. Learn more on the official website of The Villisca Ax Murder House.

4. The Mathias Ham Home Deaths

This home, built in 1856 by a Dubuque public figure named Mathias Ham, might be the most ill-fated home in the state. In 1874, Ham's wife died in the home, and he followed in 1889. Their daughter, May, passed away in the home in the 1890s. After May's death, Sarah, the last daughter of the house, had to defend the home from an armed intruder. She shot first, and the man's lamplight is still seen floating through the home, which is now a museum. Visit if you want to experience one of the most haunted places in Iowa. Here's the official website of the Mathias Ham Historic Site.

5. The Spirit Lake Massacre

The Wahpekute Sioux lived near what is now known as Lake Okoboji when there was a terrible alteraction with white settlers from March 8–12, 1857. Inkpaduta was a renegade chief, and he was known for being a strong leader with a fierce attitude. When his brother was killed by a white settler, and his tribe was starving thanks to overhunting by immigrants who were stealing his land, he retaliated. Nearly 40 settlers were killed and four hostages were taken. It was one of the last violent battles between the Natives and immigrants in Iowa.

6. The Horrors of Edinburgh Manor

Edinburgh Manor was first established as a "poor farm", and it ran as such from 1850 to 1910. During that time, there were many labor-related deaths and mistreatment was well documented. Over 80 former residents are buried in the creepy cemetery out back. After the poor farm closed, the manor was constructed to house the "incurably insane." As with most institutions in the 20th century, abuse was rampant and those at Edinburgh Manor lived inhumane and horrifying lives. Stop by the official website of Edinburgh Manor.

7. The Last Meeting of the Sioux and Sax and Fox tribes

In 1841, members of a Sioux tribe attacked a village of 24 Delaware natives on the Raccoon River, killing all but one. The Sixou tribe lost 26 of their own in the bloody battle. The nearby Sac and Fox tribe heard of this massacre, and went off in retaliation against the Sioux. The Sac and Fox chief, Pashepaho, was 80 years old. His age did not stop him, though - he gathered 500 of his best warriors and followed a trail for nearly 100 miles before encountering the merciless Sioux warriors who had killed the Delaware natives. At the end of hours of battle, 300 Sioux lay dead on the battlefield, while the Sax and Fox tribes lost just seven warriors. The last meeting of the Sioux and Sac and Fox tribes was one of the bloodiest battles in Iowa history.

Are there any other Iowa ghost stories you'd like to tell? Or do you have any little-known tidbits about Iowa history? Share them in the comments below!

If you've got to lighten the mood after reading this, check out 10 Thrilling Iowa Adventures You'll Want To Drop Everything For and get out of the house for a little fresh air.