Fort Zumwalt Park sits on land granted to Jacob Zumwalt and his family by the Spanish government in the late 1700s. The land was suitable for settlement in part because a fresh spring and creek, now known as Belleau Creek, ran through it, and Zumwalt built his family home just up the hill from the spring. Around the time of the War of 1812, local families sheltered at Zumwalt's home to protect themselves from deadly raids by Native Americans, and the spring supplied their fresh water. The reconstructed Zumwalt's Fort now stands at the top of the hill. In 1986, the spring was dammed to create Lake Whetsel, a 3.5-acre lake named for Ed Whetsel, an O'Fallon Parks and Recreation Board member and early champion of the lake. Today the spring remains hidden beneath the surface but continues to replenish the lake with fresh water.