Over 70% of japan is mountains, so the most constant landforms are mountains. Tokyo's main landforms may be mountains, rivers, lakes, vallys etc. the are also a few famous lan … d forms in Tokyo. :) In Tokyo there is alot of volcanos ..such as the one in Kobe .. which had erupted without warning in 1995. Japan is probably one of the most easily defensible countries in the world. 2  Not only is it composed of small islands, but it has a mountanious terrain in the greatest part of its main islands. 3  Mt. Fuji is located in Japan and is an active volcano there. 4  It is also Japan's highest point in elevation.