Today Her Majesty Queen Elizabeth II overtakes Queen Victoria as Britain’s longest-serving monarch and events across the area are marking the occasion.
On this day 63 years ago she started her reign at the age of 25, following on from her father, King George VI.
No Man’s Fort in the Solent will celebrate the impressive milestone with a patriotic access-all-areas lunch.
Visitors will be allowed to step aboard for a lesson on the Victorian fortress’s heritage and original features.
The fort’s secrets will be exposed for visitors to unearth and explore as they take a guided tour followed by lunch.
Tickets cost £65 and are still available at amazingvenues.co.uk/no-mans-fort departing from Gunwharf Quays at midday.
Owner Mike Clare said: ‘It’s so important for people to understand the historical importance of the forts while enjoying their beauty. And to be able to celebrate this major milestone in the Queen’s reign is special to us.’
Elsewhere, there will be footage of the Queen shown on the big screen in Guildhall Square in Portsmouth throughout the day.
The special occasion was due to be marked in Rowlands Castle this morning with the Union flag being raised at 9am at the village green.