The initial phase of the new station contained five Ferro-concrete platforms. The first two platforms, and three roads, of the new station came into use on 24th June 1909, which even though these particular works were on additional land signalled the end of South Station because it could now be demolished. Platform 4 speedily followed into service, on 25th July 1909, and this platform was, approximately, where the first platform of the former South Station had been. The new platform replacements were much straighter than the originals, which were often fan shaped, and were built in concrete with Ferro-concrete tops tastefully set off by slate copings quarried from Delabole in Cornwall. Within and under the platforms were the usual cables and pipes inherent on the running of a railway. New platforms were often connected by stairs on a long passageway to the York Road. This passageway connected to the platforms for “The Drain” as well as the booking office for the Bakerloo Line. Those wishing to leave “The Drain” for Waterloo Road were catered for via other passageways, which also gave access to the concourse.
It was along the passageway leading to the Waterloo Road that there were a variety of doors which were not always clearly understood or perhaps even noticed by various travellers - they certainly mystified me. Over the years behind those doors were located variously staff canteens, clubs for staff, rifle ranges, police offices and lost property. Both these passages were also put to other uses at various times - the one to York Road had part of it used as a free buffet for servicemen between December 1915 and April 1920 a plaque recording that over 8 million soldiers and sailors (the poor Air Force seemingly left to starve!) had free meals there. Perhaps somewhat less gallantly the other passage, to Waterloo Road, contained at some periods accommodation for emigrants who the L&SWR did not want mingling with regular passengers in their new waiting rooms.
1909 also saw a start made, at the south-eastern corner, on building new offices and public facilities behind the new concourse whilst Platform 5 came into service on 6th March 1910. It is, incidentally, from this time that the L&SWR embraced the far from innovative concept of numbering all platform faces.
from "The History of Waterloo Station"
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