Yes, there is a Lion Safari Park near Neyyar Dam in Thiruvananthapuram. And yes, the lions walk free in 10 acres of land in the small island of Marakunnam while you are taken in a safari vehicle.
The safari starts at 9 am and normally lasts about an hour. The Forest Department takes you out in a customized vehicle for the safari. Normally a safari vehicle can accommodate 15 people. There are two doors that take you into the park. The forest guards who come in the safari vehicles will open these doors one after the other. Before going in, the guards will tell you about the number of lions in the park - and that most of them were born here. And almost as a rejoinder add, 'if you are not lucky, you may not see them at all.'
We had just gone up a short way when the driver hit the sudden brake. He had spotted a lionesswho did not seem annoyed by the vehicle, nor did she get up and move out of the way. The driver backed off and took another route. Around another bend we spotted two lions, a male and a female. The guard cautioned us. The smallest sound of changing lenses irritated the lion and he roared in anger. His mate, having been disturbed walked into the forest and he followed her meekly. We followed them. The lions we discovered were about to begin their courtship. We decided to leave them to enjoy their time together and went on to see the other attractions around Neyyar.
Safari timings: 9 am to 5pm