This is the hard-standing football/basketball pitches in Grosvenor and Hilbert Park. Until 1948 this was the swimming pool, built out of the old Victorian reservoirs. Lots of photos of the swimming pool and activities can be found on the website http://www.fogh.org.uk .
The swimming pool was so deep it was very good for water polo (no one could stand on the bottom for a rest) and there was also a very unusual event held – The Top Hat, Clothes and Umbrella Race.
Today has been the warmest day of the year so far and the park was full of people relaxing, walking dogs, and children playing. The football pitch was rather deserted; as a swimming pool would it have been full on a day like this?