Titans Lair was once a records storage facility owned by Wayne Enterprises. Bruce Wayne allowed his sidekick Robin the use of the empty silo during the time when Robin helped to form the original Teen Titans.
The one-level cavern is located beneath a cliff adjacent to the Gotham City River. Special emergency exits exist at the base of the cavern, which allowed the Titans the ability to come and go in secret. It also enabled Aqualad quick access to the nearby river and Atlantic Ocean. The Lair contained a concealed helipad for the Titans Helicopter as well as living quarters, cargo lift elevators, laboratories, a warehouse and a mechanic's shop. 
The Teen Titans headquartered themselves at Titans Lair for a brief period of time, but left when they chose to work in a training program with Loren Jupiter.
Some time later, the original Titans disbanded for a two-year hiatus, but eventually reformed in response to an emergency distress signal they discovered coming from their long-abandoned lair. Doctor Light had discovered their secret headquarters and sent the signal in order to bait the Titans into a trap. After suffering a narrow defeat at the hands of Doctor Light, the Titans decided to abandon their old headquarters forever.