Mount Arayat is a potentially active stratovolcano on Luzon Island, Philippines, rising to a height of 1,026 metres (3,366 ft) ASL. There is no recorded eruption of the volcano, and its last activity probably dates to the Holocene era.
The volcano is located in a flat agricultural region at . The southern half of the mountain lies within the municipality of Arayat, Pampanga, while the north half and the mountain summit lies within Magalang, Pampanga. Ten miles to the west of Mount Arayat is Angeles City and the former Clark Air Base. Mount Pinatubo is located a further ten miles west.
It is considered a mystical mountain, the legendary home of the diwata Mariang Sinukuan, and was once believed to contain a wealth of fruit.
Two trails lead to the two peaks of Mount Arayat. Mount Arayat National Park, at Arayat, Pampanga, has a trail to Peak 1. This is the more popular trail, taking around 3-4 hours to reach the peak. Peak 1 offers views of Central Luzon, including Pampanga river, the mountains of Zambales and Bataan (W), and the mountains of the Sierra Madre range (E). On the other hand, Peak 2 can be accessed from Magalang, Pampanga, taking a similar time to negotiate.
Mount Arayat stands in the middle of the flat Central Luzon Plain, consisting of rice paddies and a typical elevation of about 15 to 30 meters MSL. The mountain is topped by a circular volcanic crater about 1.2 km in diameter, much of which has collapsed on the western and part of the northern rim due to erosion. This has resulted in a breached crater which opens in a west-northwest direction. This area is the apparent source of a major debris-avalanche deposit that forms hummocky terrain beyond the west and northwest sides of the volcano. The 1027-meter summit stands on the northeast side of the breached crater, known as North Peak, while the 984-meter Pinnacle Peak is located on the southeast crater rim . Post-collapse activity formed an andesitic dome known as White Rock in the collapse amphitheater.
There are no cultural records of historical eruptions. Weak steaming is currently present on the NW side of the summit.
Rock types are basalt and andesite.
The only rocks reported to have been dated are 0.53 and 0.65 million-year-old basalts. These predate the crater collapse and formation of the lava dome, which could have occurred in the last 2000 years.
Fumarole activity is reported on the NW side of the summit.
The Global Volcanism Program lists Mount Arayat as Holocene?
Philippine Institute of Volcanology and Seismology (PHIVOLCS), list Mount Arayat as Inactive.