It is now possible to accurately sketch both parts of Colter’s famous journey. Firstly, from Fort Manuel he reached the Yep-pe Indian camp and returned to the mouth of the Bighorn River where Fort Manuel was built, exactly as the map depicts. It is because of the accuracy of this section of the Map of 1814 that Colter’s Yellowstone course may be now traced like tracks in the snow. Secondly, from the Yep-pe Indian camp, Colter ascended “Elk-Wapiti Creek” to its source; then crossing a range he came upon a mitten-shaped mountain, which he labeled “fossil.”[45] From this landmark he probably descended Pass Creek to Thorofare Creek, which he followed to the Upper Yellowstone River. Then he ascended Atlantic Creek and crossed the Continental Divide at Two Ocean Pass. From here he descended Pacific Creek, skirted Big Game Ridge, and crossed the South Fork of Snake River, within the present confines of the Park. Thence, along Chicken Ridge, from whence he could frequently view South Arm, he headed toward Flat Mountain Arm, crossed Solution Creek, and struck West Thumb.[46] The validity of this itinerary is wholly sustained by the genuine features of this area as they appear upon the Map of 1814. Indeed, the route seems obvious and indisputable in view of the actual conditions existing. There are alternative routes within certain limitations. On a crude map where there are numerous similar streams various combinations are possible.[47] [Illustration: Section from map of 1814 depicting Lewis and Clark route. Its legend reads: “A map of Lewis and Clark’s Track, Across the Western Portion of North America, From the Mississippi to the Pacific Ocean; By Order of the Executive of the United States in 1804, 5, 6. Copied by Samuel Lewis from the Original Drawing of Wm. Clark.”] Leaving West Thumb, Colter circled the Lake to its outlet and followed it to the Hayden Valley thermal area. Dragon’s Mouth and the Mud Volcano were undoubtedly features contributing to the impression he carried away and transmitted to others. Even the “Hot Springs Brimstone” characterization on the Map of 1814 mildly suggests violent thermal activity. The phrase also suggests that Colter mapped a geyser basin.[48]