Atlantic Creek is one of two rivers formed at the hydrologically unique site of the Parting of the Waters. The creek begins in the Teton Wilderness of Bridger-Teton National Forest in the U.S. state of Wyoming near the southern border of Yellowstone National Park. It originates directly on the continental divide from North Two Ocean Creek, which splits roughly in half at the Parting of the Waters. One half of the flow becomes the headwater of Atlantic Creek, while the other half becomes the source of Pacific Creek.

Atlantic Creek, as its name suggests, ultimately flows into the Atlantic Ocean 3,488 mi (5,613 km) away. From the Parting of the Waters, it flows northeast over five miles of wilderness through the alpine valley of Two Ocean Pass and ends it short run into the Yellowstone River approximately 15 mi (24 km) southeast of Yellowstone Lake.

Following the flow of water to the Atlantic Ocean, the Yellowstone River meanders north in its river plain feeding Yellowstone Lake from the south and leaving the lake's northern edge. The river continues north going over both Yellowstone Falls, through the Grand Canyon of the Yellowstone, and eventually flows into the Missouri River in far western North Dakota. From the confluence of the Yellowstone and Missouri, the Missouri flows mostly south across the Dakotas. It then forms the borders of Nebraska, Iowa, Kansas, and Missouri before finally flowing east into the Mississippi River which empties into the Gulf of Mexico in Louisiana.

Atlantic Creek's twin, Pacific Creek, takes the other half of flow from North Two Ocean Creek. It flows further than the relatively short run of Atlantic Creek, emptying at Moran, Wyoming over 20 miles to the southwest into the Snake River below Jackson Lake Dam and ultimately the Pacific Ocean 1,353 mi (2,177 km) away via the Columbia River.

• Divide Creek, in the Canadian Rocky Mountains
• Teton–Yellowstone tornado, an unusual 1987 F4 tornado that passed over neighboring Pacific Creek