Only during Benjamin Mazar's excavations between 1968 and 1977 was it discovered that the pier was in fact the western support of a single great arch. The uncovered pier, long and wide, was preserved to a height of . Within its base were found four small hollow spaces, possibly for shops opening onto the Herodian-era Tyropoeon street that passes beneath the arch. The lintels of these survive in place and are themselves arched to relieve pressure from the weight of the pier's superstructure. Mazar's excavations have revealed that the same pier was also the eastern external wall of a monumental building which Mazar suggested was the archives of Jerusalem mentioned by Josephus. South of the building, excavators found the remains of six vault-supporting piers, gradually decreasing in height southwards over a distance of . These vaults, the building and Robinson's Arch, all supported a monumental flight of stairs which led the street up and over the Typropoeon street to the gate of the Royal Stoa at the top of the Temple Mount platform. Numerous stone steps, some still adjoined, were also found nearby.