(Covers information from Anderson's universe)
The Umbrella Corporation Headquarters was a huge subterranean facility located under Tokyo, Japan.
The corporate headquarters survived the global T-virus outbreak for years as one of the few remaining, uncompromised facilities. Due to the risks of being outside, Umbrella Commitee meetings were held via holographic messages, with the company's chairman - Albert Wesker - representing this facility.
Alice, a rogue former-Umbrella employee, attacked the facility with an army of clones created by Dr. Sam Isaacs. Killing the sentries guarding the facility from its office block facade, they began fighting their way in during the thirty minutes Umbrella spent trying to re-establish communications.
The facility was later destroyed when Wesker detonated a bomb inside the facility, killing all of the clones and surviving operatives in the process.
It is left vague as to whether the Tokyo facility was always the corporate headquarters, or if it became such as a result of the viral outbreak.