There are over 30 rivers in the United States that flow north, and over 60 throughout the entire world. The Nile, which is the longest river on Earth, is arguably the most famous river that flows in a northerly direction.
Rivers that flow north are a difficult concept for some to grasp. Rivers flow downhill from their source, and usually the source is somewhere in the mountains located north of the river's mouth. However, if the source happens to be south of the mouth, the river then naturally flows in a northward direction.
Some well-known rivers in the United States that run north include the St. John's River in Florida, the Willamette River in Oregon and the Monongahela River, which starts in West Virginia and flows into Pittsburgh. Here, the Monongahela River joins the Allegheny River and the two become the Ohio River. The New River starts in North Carolina and flows through Virginia and West Virginia. Geologists state that prior to the Ice Age, this river flowed in a southerly direction.
In other parts of the world, some northern-flowing rivers are the Rhine, which flows from Switzerland between France and Germany, the Orinoco River in Venezuela and the Ems River in Germany. The famous Ganges River in India has a number of tributaries that flow in a northerly direction, including the Chambal and Betwa.