Verified answer

The Rhineland is a large N-S area that runs all along Germany's western border with France, Belgium and part of Netherlands because it runs along the long Rhine river along or near the German border.

The Ruhr is a much smaller area within the Rhineland near it's north tip on the east bank of the Rhine near the border with the Netherlands. It was Germany's main military industrial factory area in WWI.

Forget WWI and WWII. Rheinland is traversed by the River Rhein. The Ruhrgebiet is traversed by the River Ruhr.

Ruhr Rhineland