Popo Poco Volcano
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Popo Poco Volcano (ポポ コポ 火山, Popo Kopo Kazan) is a volcanic mountain located close to Popo Poco Village. The villagers believe that there is a mountain god who prevents the volcano from erupting, and so they create a huge stone statue that represents this god and worship it (although this idol statue represents a god, it actually looks like a Demon).
Popo Poco Volcano appeared in "Walking Their Own Ways" and "Hotter than Lava". Tenshinhan, Chaozu, Kuririn, and Yamucha visited Popo Poco Village prior to their training with Karin and saved it from lava when the volcano erupted.
Dragon Ball GT
Popo Poco Volcano was the location where Nuova Shen Long materialized after the division of Black Smoke Shen Long into the seven Evil Dragons during the Shadow Dragon Saga. The arrival of Nuova Shenron caused the volcano to erupt once again in "The Shadow Dragons".