I visited the lion habitat a couple of times while staying in Vegas. Both times I visited it was lion cubs in the enclosure, so they were actively chewing on toys, playing with each other, and trying to get their trainers to play with them. The overhead announcement explains that the lions are only brought to the air purified sound proof enclosure four hours a week. I kinda envied the air purified part of it. I took several photos with the flash off - I would recommend that not only because it will bother the lions but also the enclosure is glass so taking a picture with flash will only give you bright white spots in your pictures. There's plenty of light for a good quality shot without flash. It does get crowded, so be patient and you will have a chance to get close to the glass for optimal viewing.