If you are asking about tributaries... the first river that flows into the Mississippi north of St Louis is the Missouri, but the Missouri is not really considered to be a tributary. It's a major river unto itself. Further north, the Illinois River flows into the Mississippi.
East Saint Louis is Illinois, on the east side of the Mississippi River, opposite Saint Louis, which is in Missouri.
Saint Louis
The Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.
The Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.
The Missouri River joins the Mississippi very near St Louis.
The Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.
The major river that flows into the Mississippi River just north of St. Louis Missouri is the Missouri River. When the rivers join, they become the 3rd largest river system in the world.The Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.St. Louis, Missouri is located near the junction of the Missouri River and the Mississippi River.Ohio RiverThe Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.The Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.
Mississippi River
Saint Louis
The Mississippi River.
They meet near St. Louis, Missouri.St. LouisThe Missouri River flows into the Mississippi River just north of Saint Louis, Missouri.
First saint Louis