Once. The agricultural exhibition hall is the venue of the agricultural products fair, which is held once a year. The National Agricultural Exhibition Hall was approved to be established in the State Council in June 5438+0957, and was completed and opened in September 1959. It is one of the "Top Ten Landmarks of the Capital" built to celebrate the 10th anniversary of the founding of New China, and enjoys the same fame as the Great Hall of the People, the National Museum and the China People's Revolutionary Military Museum.