Because of isostasy a mountain will ultimately answers

lsostasy denotes the theoretical balance between Earth's crust and mantle and explains how mountains are compensated by masses of smaller density under the mountains while oceans are compensated by masses of higher density under the water.  Gravity controls the isostatic adjustment of Earth's crust.

Because of isostasy a mountain will ultimately be eroded to near sea level

river is shown in this type of map