Sir Nicholas Grimshaw - last week awarded the UK's highest honour for architecture - says that of all the buildings he has designed, he is most proud of the former Eurostar terminal at Waterloo International.
Between 1994 and 2007 Waterloo International was the London terminal for Eurostar's trains to Paris and Brussels.
For more than a decade the five platforms were largely disused, with taxpayers picking up a large bill for security and maintenance, but since last December South Western Railway trains on the Windsor lines have been making regular use of the platforms.
Asked by John Wilson on Radio 4's Front Row to pick out the building that he is most proud of, Sir Nicholas said: "Well I think I would always go back to Waterloo actually.
"Although it's not functioning as an international rail terminal, it's still there."
He added: "It's wonderful to feel that it can be brought into full use and will continue as a useful structure.
"Every building ought to be able in some way to be used for other things.
"Architects when they put in a planning application should be made to put in suggestions for alternative use for their building, so as to prove that it is going to be useful over time."
Sir Nicholas Grimshaw last week received 2019 Royal Gold Medal, the UK's highest honour for architecture, awarded by the Royal Institute of British Architects (RIBA).
Given in recognition of a lifetime's work, the Royal Gold Medal is approved personally by the Queen and is given to a person or group of people who have had a significant influence 'either directly or indirectly on the advancement of architecture'.
At the end of last year Time Out Market was named as the anchor tenant of the new shopping and leisure complex currently being created in the former Eurostar departures and arrivals lounges below the platforms.
Featuring 500 seats, 17 eateries and three bars, Time Out Market Waterloo is due to open in 2021.
"Time Out Market will be a fantastic addition to London's South Bank – this is a much-loved neighbourhood with fantastic restaurants, bars, museums and theatres," said chief executive Didier Souillat.
"London is home to an outstanding and wonderfully diverse culinary and cultural scene of which Time Out Market will showcase the very best.
"It is all about the democratisation of fine dining: making it casual, and casual extraordinary. Time Out Market will be a place where locals and visitors can really get to know and experience the city."
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