H.E. Malden gives the following account of the demolition and the relocation of the porter's lodge, in his 1902 history of Trinity Hall, p.243:

In 1872 it was found that the very old buildings about the Porter's Lodge, on the east side of the Porter's or smaller court, were in hopeless decay. Space was wasted by their lack of arrangement, and, with the exception of one set, the rooms in them were not good. They were completely pulled down, and the present buildings put up by A. Waterhouse as architect. The alterations involved the stopping up of a very steep staircase which ran up from the larger court, close to the passage between the two courts. The mark of its entrance is still clearly seen in the wall. The rooms over the archway, which had long ago been the old Library, were approached, among others, by this staircase.

At the old entrance the main archway had been long built up and plastered over so as to be scarcely visible. The old postern-gate was used as an entrance. When the old building was demolished, Mr. Latham caused this archway and the postern to be carefully removed and built up again at the entrance to the garden from Garret Hostel Lane, where they now stand. Though a possible entrance from the street was kept under Waterhouse's new building, the Porter's Lodge was at this time transferred to its present place, under the archway leading through Salvin's buildings into the larger court. It is an improvement, partly because a person entering the College is not immediately confronted by the lodging-house style of architecture of the 1823 building, partly because this was the natural entrance of the College for persons going to the kitchens or butteries, and for those who wanted to come for good or bad purposes to undergraduates' rooms, and it was well that they should pass the porter.

The book also contains another view of the gateway, facing page 32

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