The enclosure is almost triangular in shape, the western and eastern sides being approximately 250 feet long, and the southern side around 200 feet long. The area is about 2500 square feet, or as Chris says half an acre.
Fences are checked every morning before the lions are given access to the enclosure. The foundations are old concrete road traps left over from World War II. This enclosure was the first open air lion enclosure to be built, and before Longleat Safari Park opened in 1967, local council officials visited Chester Zoo to see for themselves how big cats could be safely housed behind a wire mesh fence.
They are fed six days a week, (not Fridays) on fresh cow and horse meat, also given are whole rabbits, chickens and turkeys. The food is sometimes sprinkled with vitamin powder.
The house was built in 1984 and consists of inter-connected dens one of which has public viewing. Straw bedding is provided.
The enclosure contains many trees, some are protected and some can be used as scratching posts. On the eastern side of the enclosure where the path between Jubilee Square and the Fountain shop runs, there is a plaque on the wall of the stables pointing out where the lions have left claw marks in the brickwork. This area was part of the original enclosure.
There is also a raised platform on which the lions can sit
The lions must be vaccinated against feline enteritis and cat flu, at 10 and 18 weeks old, and once a year thereafter. New lions coming into the zoo have a health check.
I expect cleaning is done every day apart form when a female has cubs in her den.
That's all I know at the moment.