The Volcano as it makes its debut in the fifteenth episode, Bouncing Ball.
The Volcano is a minor location in Dora the Explorer. It only appears in seven episodes: Bouncing Ball, Roberto the Robot, Swiper the Explorer, We're A Team!, Dora Saves The Crystal Kingdom, School Science Fair (though not as a location), and Dora and Diego in the Time of Dinosaurs (named Dino Mountain).