From the park entrance at the side of the main road, transport (50 Cordobas/US$3 one-way) can take you up the hilly road to the edge of the active Santiago crater. It last erupted in 2000, toppling one of the previous viewpoints into the crater, but the park is otherwise well organized and safe. Views of this massive hole in the ground are impressive; there are also paths that lead to views of a large crater lake, a guided walk to a cave, and a good information centre.
VolcĂˇn Masaya National Park, Near Masaya
National Park, Hiking
Bus to entrance 18