Potomac. Savannah. Altamaha.
At that early point in the history of colonial Africa most borders were based on geographical features, primarily rivers.
The Southern Colonies had lots of watery landform's. Such as bays, rivers, lakes, and swamps.
The thirteen colonies were located along the eastern coast of what is now the United States, stretching from New Hampshire in the north to Georgia in the south. They were divided into three main regions: New England (including colonies like Massachusetts and Rhode Island), the Middle Colonies (such as New York and Pennsylvania), and the Southern Colonies (including Virginia and South Carolina). These colonies were established by various European powers, primarily England, and had defined borders that often followed natural landmarks like rivers and mountains or were determined by colonial charters. The boundaries were not always precise and often shifted due to conflicts and negotiations with Native American tribes and other colonial powers.
Wabash, Ohio and Mississippi respectively
The Southern Colonies had various types of land forms including barrier islands, mountains, and rivers. They also had rolling hills and sedimentary rock.
Fertile soil, harbors and rivers and a long growing season
Economy in The Southern Colonies was based on plantations and slavery. The main crops that were grown were Indigo, Tobacco, Wheat, and Rice due to the easy irrigation from nearby rivers.
none of the rivers form the southern border of Indiana, but the Ohio river forms the southern border of Ohio.
Land, and Mountains
They had rivers, the Atlantic Ocean, trees, good soil, and other stuff. :0)
Both are landlocked countries in their continents, each with a river as southern border.
Because it made bulk transport of cotton to the coast and from there overseas the easiest. Cotton was an export industry, and the Southern colonies were untill the Civil War the biggest producers in the world.