Mississippi
Spain forms the eastern boundary of Portugal.
The southern half of the eastern boundary of Alabama is the Chattahoochee River.
The Atlanic Ocean
Minnesota.
The states of Iowa, Missouri, and Arkansas have their eastern borders on the Mississippi River. The Mississippi River borders seven other states.
The Connecticut River
The Mississippi River is the East boundary for Arkansas.
The country is Eritrea, and it's eastern boundary is formed by the Red Sea.
Two rivers partially form Illinois State's Eastern boundary. The Wabash River is one river that forms Illinois' boundary. The Ohio River is the other river that forms the state's boundary.
Mississippi River
chattahoochee river