Mount Aso is an active volcanic mountain located on the island of Kyushu in Japan. It is part of the Aso-Kuju National Park and is one of the most popular tourist attractions in the region. The mountain is approximately 1,592 meters high and has five main peaks, the largest of which is Nakadake.

Mount Aso is considered one of the world's largest calderas, with a diameter of approximately 25 kilometers. The caldera was formed around 90,000 years ago during a massive eruption. The mountain is still active and has frequent small eruptions, which means that sometimes visitors cannot access certain parts of the park.

The area around Mount Aso is home to many natural hot springs, known as onsen, which are a popular attraction for visitors. There are also several hiking trails around the mountain and a cable car that takes visitors to the summit of Mount Nakadake, where they can see the active crater.

One of the main attractions of Mount Aso is the opportunity to see volcanic activity up close. Visitors can watch as smoke rises from the crater of Mount Nakadake, and they can feel the heat of the steam that rises from the ground. The area around the mountain is also known for its beautiful natural scenery, including lush forests and grassy plains.