"Go to the southwest gate of the White House complex, present the guard with identification, and state your business. If you are on the appointment list, an escort will be called. Walk up West Executive Avenue and turn right into the West Basement entrance; another guard will check your pass for White House access. Take the first right, down a few stairs. To the left is the White House Mess; on the right is a locked door. Behind these layers of security is the White House Situation Room (WHSR), a conference room surrounded on three sides by two small offices, multiple workstations, computers, and communications equipment. The conference room is soundproofed and well appointed but small and slightly cramped. The technical equipment is up to date, though not necessarily "leading edge"; every square foot of space is functional. Visitors typically are impressed by the location and technology, but they are often surprised at the small size. While it is widely known that important meetings are held here, the importance of the WHSR in the daily life of the National Security Council (NSC) and White House staff and its critical role in Washington's network of key national security operations and intelligence centers are less understood. This paper is intended to fill that void. We believe there is a longstanding need within middle and senior levels of the Intelligence Community (IC) for a basic understanding of NSC and White House functions and how current intelligence information is provided to key decision makers, including the President."
Center for the Study of Intelligence: https://www.cia.gov/library/center-for-the-study-of-intelligence/index.html
Studies in Intelligence (Semiannual Edition 1997), no.1