Olympic Tower, also known as the Office of Naval Intelligence Headquarters (ONI HQ), was a building at Fleet Command Headquarters in the city of New Alexandria, Eposz on the planet Reach. It was one of FLEETCOM HQ's main buildings for special projects and high-ranking officials, including those with ONI. At 2,250m, it was one of New Alexandria's highest buildings. It was quite prestigious a tower to be in, and in particular, the corner offices provided a wonderful view of the surrounding area.
Dr. Catherine Halsey, leader of the SPARTAN-II and Mjolnir Powered Assault Armor projects, was offered a corner office in this tower when her projects were at its heights. Yet she declined, and eventually her office underneath Sword Base provided some isolation and peace from those who wanted to bother her. Eventually Sword Base proved to be her salvation as Olympic Tower and almost all of the surface of Reach was glassed by the Covenant, but Dr. Halsey was able to stay safe until Noble Team was able to escort her to CASTLE Base.
During the Fall of Reach, the Olympic Tower was the center of operations for the evacuation effort around New Alexandria, but later came under attack after the Covenant zeroed its position. In the later stages of the evacuation, Colonel Urban Holland requested that all personnel be evacuated from the building immediately.
There was a fallout bunker on Sublevel Two of the facility, where Noble Team headed after the Covenant began glassing the city. The tower also had a small retractable landing pad on an upper floor. On the way to the fallout bunker, Kat was shot through the skull with a Needle Rifle and killed.
- The building shares its name with a real-life Olympic Tower, a skyscraper in New York City.