GEOPHYS
"There used to be a large pile of the arcade's columns etc on the green space bordered by Warwick Street and Stoddart/Portland St. Drive along Warwick - in front of the Loco and there is a large lump in the surface. That's where they were, I assume they are still there, buried to confuse archaeologists of the 25th century "

http://www.skyscrapercity.com/showthread.php?t=1482279&page=15
The site opposite the Loco in 2016:
The site on the corner of Warwick Street and Newington 2016:
RESULTS OF THE GROUND PENETRATING RADAR: (OBSERVATIONS ON THE DAY SHOWED THAT THERE ARE NO BUILDING REMIANS BELOW THE GROUND ON THE SITE OPPOSITE THE LOCO ON WARWICK STREET).
There are anecdotal stories that to point towards specific sites at the City Stadium in Newcastle Upon Time as being potential burial sites for the stones of The Royal Arcade. We have started a small survey of the site with the Geography department at Northumbria University.