 So one of the biggest differences between this map and the 1803 map that they took with them when they traveled is this area here, including the course of the Missouri River, which previously had just been shown as a dotted line, and here has been elaborated in much more detail. This was made in the winter of 1804 to 1805, and temperatures in the fort were below 20 degrees, even dropping below 40 degrees. And while they were stationed there, here you have William Clark