The Arriandeaux log cabin in Dubuque is the oldest building west of the Mississippi River. It was built before 1828 by French fur trader Louis Arriandeaux. Fur trading and lead mining brought settlers to Iowa in the early 1800s. The cabin features a dog trot, or breezeway, separating two sides. This style was more common in the south. Both sides have a stone fireplace. Historians think one side would have been for business and the other a residence. Settlers who didn't plan to stay very long lived in a badger hole. It would have been dug right into the dirt and covered with a tarp roof. It's easy to forget how fast cities were built in those days. Iowa's population doubled every few years when Iowa first became a territory.