After the September 11 attacks in 2001 , the chamber was closed to tourists for almost two years due to security concerns ; tour groups would have to pass close to the current Senate chamber and the office of then-Senate Majority Leader Bill Frist . It was later reopened after tightened security measures were put into place , with visitors being observed by two Capitol Police officers posted outside the room and allowed to " quickly file through the room " only when the Senate is not in session ( usually Monday mornings and Friday afternoons )
September 11 attacks
September 11 attacks
Old Senate Chamber