The Portsmouth landmark was voted for by nine per cent of people in a survey.
Top was Highclere Castle – better known as Downton Abbey – which received 43 per cent of the votes.
Next was Winchester Cathedral with 24 per cent.
The survey was done by groundworks firm Rudridge.
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Its operations manager Darren Price said: ‘Highclere Castle is an excellent example of unique architecture and materials used to create something truly sensational and visually stunning – it’s no surprise it has been voted Hampshire’s most beautiful building.’
Other Hampshire buildings of significance that featured high up on the list were Jane Austen’s House Museum in Chawton near Alton with 12 per cent and Mottisfont Abbey near Romsey, also with 12 per cent.
A spokesperson for Highclere Castle said: ‘We’re absolutely delighted that Highclere has been chosen as the county’s favourite landmark. The castle is enjoyed by so many, with people travelling from far and wide to visit the beautiful and iconic setting – thank you to everyone who voted.’