The loess soils that make up much of the surface of the park have shaped both the landscape and the history of Vicksburg. The loess deposits of western Mississippi originated to the north during the Pleistocene Ice Age. As the glaciers in what is now Canada and the northern Untied States moved, they would grind up the bedrock and other rock debris into a fine flour-like soil. As glaciers melted, this soil was washed down the Mississippi River and deposited on flood plains. Once dried, this powdery soil was picked up by wind before being deposited a second time up on the high eastern bluffs of the river. The loess bluffs trend north-south throughout the state, bordering the river to the south and the Delta to the north.
The loess soil has several defining characteristics. It is well drained and rich in nutrients, making it ideal for agriculture, such as growing cotton. It also prefers a vertical orientation and erodes heavily when it is not cut at 90 degree angles. Over the years, the loess soil has created many problems for infrastructure along the loess bluffs of Mississippi.