Tianmen Mountains are in the northern Hunan Province of China, near the city of Dayong. (Many people are confused by the name Tianmen that is similar to the famous Tiananmen Square, in Bejing, thousands of miles away)
To reach the summit you can take the Tongtian (avenue toward heaven) highway which has 99 sharp turns. At its end you have to climb the Tianti (ladder to heaven) stairs which has 999 steps. It is perhaps one way to reach heaven, scared to death by the road and out of breath from climbing!
But all the effort is worthwhile.