The North American continent is home to many rivers, four of which are the NIAGARA, Mississippi, Hudson, and COLUMBIA Rivers. The NIAGARA River is a 7-letter river that flows from Lake Erie to Lake Ontario. The Mississippi River is an 11-letter river that is the second longest river in the United States and is known for its importance in the history of the country. The Hudson River is a 6-letter river that runs through New York State and is a major part of the Atlantic Ocean estuary. The COLUMBIA River is an 8-letter river that is the largest river in the Pacific Northwest region of the United States. Finally, the St. Lawrence River is a 10-letter river that forms part of the international boundary between Canada and the United States. All of these rivers are important to the North American continent and have played a significant role in the development of the region.