
Crowley's Ridge (also Crowleys Ridge) is a geological formation that rises 250 to above the
alluvial plain
An alluvial plain is a largely flat landform created by the deposition of sediment over a long period of time by one or more rivers coming from highland regions, from which alluvial soil forms. A floodplain is part of the process, being the s ...
of the
Mississippi embayment
The Mississippi embayment is a physiographic feature in the south-central United States, part of the Mississippi Alluvial Plain. It is essentially a northward continuation of the fluvial sediments of the Mississippi River Delta to its conflu ...
in a line from southeastern
Missouri
Missouri is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it is bordered by eight states (tied for the most with Tennessee ...
to the
Mississippi River
The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it ...
near
Helena, Arkansas
Helena is the eastern portion of Helena–West Helena, Arkansas, a city in Phillips County, Arkansas. It was founded in 1833 by Nicholas Rightor and is named after the daughter of Sylvanus Phillips, an early settler of Phillips County and the ...
. It is the most prominent feature in the
Mississippi Alluvial Plain between
Cape Girardeau, Missouri
Cape Girardeau ( , french: Cap-Girardeau ; colloquially referred to as "Cape") is a city in Cape Girardeau and Scott Counties in the U.S. state of Missouri. At the 2020 census, the population was 39,540. The city is one of two principal citi ...
, and the
Gulf of Mexico
The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United S ...
.
This narrow rolling hill region rising above the flat plain is the sixth, and smallest, natural division of the state of