If you're talking about just in US territory, then west.
There are more mountains west of the Mississippi River!
There are more mountains west of the Mississippi River. The mountains west of the Mississippi River are also higher than those east of the river.
there are more on the east than the west.
Is the mississippi river east or west of the rocky mountains?
west
The Rocky Mountains are WEST of the Mississippi river
west
its amazingly west
West at least if you mean real mountains.
there are mountains west
yes. the Rockies
East of the Rocky Mountains.