The castle of Ayrf is one of the most important cultural monuments in the region of Hail. Reforms continued during the era of Al Rashid until it reached its current form during the reign of Saudi Arabia, where he was exploring the crescent of the month of Ramadan and was called the Ramadan cannon
The castle is built on an area of 440 square meters.The historic museum known as the castle of Ayrf, which is located at the top of a mountain with a height of 650 meters, known as Mount Ayrf, which is attributed to the name of the castle, the castle was built of mud, and was equipped with towers The openings to monitor the enemies and defend its inhabitants from the dangers of adversaries and invaders until it became the safe guard of the city and its inhabitants, and then rolled by additions and buildings in the era of the Rashid, until it reached its current form, which is a rectangular and medium-sized castle surrounded by a strong wall and equipped with holes to drain rainwater. The castle is equipped with all the needs of cleats, where there are places to sleep and other storage and chapel and toilets, in addition to the large number of towers and control openings and defense inside, which number 30 towers, the castle is characterized by large wooden doors and carved inscriptions of the region as well as the height of the castle tower, which takes a conical shape Graduated with dimensions of 40 meters and 11 meters per side. In modern times, the castle has been transformed into a site from which to explore the crescent of the month of Ramadan and launch a cannon to alert fasters when it is time to break their fast, before turning into a tourist attraction at the moment.