The Bromo-Tengger-Semeru National Park is like the Grand Canyon of Indonesia-in East Java. 

In pre-history there was an enormous volcano here. At some point it erupted leaving a massive crater 14 kilometers across.   In the middle of this ancient mega-crater are three newer volcanic craters—Mounts Bromo—still very active,  Batok & Kursi.  These triplet craters are surrounded by sea of sand that’s covered most mornings by a mysterious feeling blanket of fog.