Children build mud forts on the banks of the Kansas River Tuesday, Aug. 12, 2014 as part of the Civil War on the Western Frontier activities in Lawrence.

photo by: Mike Yoder

Participants in the "Kids, Let's Build A Mud Fort" which is part of the Civil War on the Western Frontier activities in Lawrence, construct shelters along the Kansas River Tuesday, Aug. 12, 2014.

photo by: Mike Yoder

Marina Profeti, 8, Lawrence, tosses dirt out of a hole as she participates in a mud fort activity on the banks of the Kansas River Tuesday, Aug. 12, 2014.

photo by: Mike Yoder

Participants in the "Kids, Let's Build A Mud Fort" dig out protective areas on the banks of the Kansas River Tuesday, Aug. 12, 2014.

photo by: Mike Yoder

Isabella Vermooten, 10, Rio Rancho, NM., who was in Lawrence visiting her grandmother Ginger Vermooten, participants in building a mud fort on the banks of the Kansas River Tuesday, Aug. 12, 2014. Before the Civil War, when Kansas was a western territory, Lawrence residents built mud forts to use in case of raids by pro-slavery guerrillas.

photo by: Mike Yoder

Dale Michael, 11, Baldwin, takes a rest during the "Kids, Let's Build A Mud Fort" activity Tuesday, Aug. 12, 2014. Participants constructed the shelters as part of the Civil War on the Western Frontier activities in Lawrence.

photo by: Mike Yoder

Participants in the "Kids, Let's Build A Mud Fort" which is part of the Civil War on the Western Frontier activities in Lawrence, raise the flag on their shelters on the banks of the Kansas River Tuesday, Aug. 12, 2014. Before the Civil War, when Kansas was a western territory, Lawrence residents built mud forts to use in case of raids by pro-slavery guerrillas.