birds view

its written above that the best place to have a great bird's eye view of the city is located at the junction of Shenzhen Dong Lu, Jiefang Lu and Baoan Nan Lu - the Diwang Mansion. The lift will take to the top of this 384-meter-high building in 50 seconds, where could have the best viewing angle. could u please tell me how to get there??? n is that free attrction???