Dunstable Downs is an area of chalk grassland, downland and farmland in Bedfordshire within the Chilterns Area of Outstanding Natural Beauty (AONB). Some 178 acres (73 hectares) have been designated by Natural England as a Site of Special Scientific Interest (SSSI), because of the quality of its chalk grassland. The Downs, managed by the National Trust, provide panoramic views over the Vale of Aylesbury and along the Chiltern ridge, including classic views of Ivinghoe Beacon. A modern visitor centre, the Chilterns Gateway Centre, is located atop of the Downs, alongside an unusual 'wind-catcher'. Historical monuments on the Downs include the Five Knolls, a group of round barrows, and the Robertson Memorial. The nearby village of Whipsnade has a unique Tree Cathedral and the extensive acres of Whipsnade Zoo. The National Trust manages the Downs to encourage delicate wild flowers, which thrive on the thin chalky soils. The display of orchids in May and June is stunning. Sightings of red kites flying above the Downs are increasingly common. They must share the skies with gliders, launched from the London Gliding Club at the foot of Dunstable Downs, and paragliders and hang gliders, which make use of the updraught on the western slopes of the Downs. Dunstable Downs is widely used by walkers, joggers, cyclists and horse-riders and is a beauty-spot, where people come to look at the views, enjoy picnics, exercise dogs or fly kites. The National Trust organises family events on the Downs, including the annual Kite Festival, while Regiment Fitness holds Warrior Adrenaline Races, in which competitors run over a 5-km or 10-km hilly and muddy course on the Downs. In Dunstable Downs through the Seasons, local photographer John Bishop presents photographs covering the landscape, nature and activities on the Downs throughout the four seasons of the year.