Armed Forces Day celebrations take place across UK

Armed Forces Day has been marked with celebrations across the UK.

Hundreds of veterans, serving personnel and cadets joined the Princess Royal and the prime minister for a day of military demonstrations in Stirling, which led the events.

A huge parade of services personnel - young and old - kicked off the proceedings, marching from Stirling Castle to the event grounds nearby.

A Red Arrows display was among a packed timetable of entertainment.

Representatives of the Army, Navy and Air Force took part in the event, the centrepiece of celebrations going on all over the country and at British military outposts abroad.

The day was also marked at Wimbledon, where services personnel were honoured on Centre Court.

Prime Minister David Cameron and Scotland's First Minister Alex Salmond were both on hand as Princess Anne took the salute from a group of veterans leading the 1,000-strong parade from Stirling Castle at 11:30 BST.

They headed through the Old Town and were joined by cadets and serving personnel at the Albert Halls, before making their way to the Royal Parklands.

Tanks and military vehicles were on display throughout the day, with demonstrations by Sea King and Apache helicopters.

Plane enthusiasts were treated to seeing the Lancaster and Spitfire in flight, along with more modern Typhoon and Tornado jets. A demonstration by the Red Arrows stunt team closed the event.

Other displays included Royal Marines fast-roping from helicopters, pipe bands, a parachute display by the Army's Red Devils, an artillery gun salute and troops staging a ground assault complete with casualty evacuations.

The event came on the same day Mr Salmond appointed Scotland's first Veterans Commissioner to provide greater support for services personnel.

Meanwhile, the Queen attended a service honouring volunteers who served in World War One, 100 years on from the assassination of Archduke Franz Ferdinand in Sarajevo which led to the outbreak of war.

A display by the elite Red Arrows closed the day's events

More than 1,000 veterans, cadets and serving personnel took part in the march in Stirling, which led celebrations

Princess Anne and the prime minister greeted service personnel in Stirling

An artillery gun salute was fired from Stirling Castle

The armed services were also honoured on Centre Court at Wimbledon

A message from the Queen to mark the event praised the men and women of the forces as "admirable examples of professionalism and courage".

She added: "Then as now, they perform their duties in often the most difficult and dangerous of circumstances, both at home and overseas."

Politicians were united in voicing their support for the armed services, with rivals Mr Cameron, Ed Miliband and Mr Salmond all present in Stirling.

Mr Cameron said: "A lot of people want to show their respect for the armed forces, what they do, the values they bring to the country and also to say thank you to their families."

In a message on Twitter, Mr Miliband added: "Today we recognise the huge contribution the men and women of our armed forces have made to Britain. Thank you."

Mr Salmond said the events signified the respect for serving soldiers, veterans and military families and their "selfless service to preserve our democratic freedoms".

Air Chief Marshal Sir Stuart Peach, vice chief of the defence staff, said the event was a "very special opportunity" for the services to "unite with the society that we serve".

Organisers estimate the Armed Forces Day event will earn about £1m for the local economy, while boosting Stirling's reputation as a tourist destination.

Armed Forces Day is part of Stirling's "Big Weekend", which includes the Bannockburn Live battle re-enactment weekend, the Pipefest pipe band competition, and a night of open-air performances, entertainment and street art at Stirling's Big Night Out.

Thousands of spectators flocked to Stirling to see explosive military displays

Prime Minister David Cameron was in attendance at the opening parade

First Minister Alex Salmond and Labour party leader Ed Miliband were also in Stirling