Service personnel took part in a parade and a service was held to remember those who died in conflicts.
Military flypasts were also held, while hundreds of bikers from across Europe converged on Alrewas to raise funds for the Royal British Legion.
Organisers said it attracted more people than last year's event, which 3,500 people attended.
Lt Col Alistair Fawcett, commanding officer of 22 Signal Regiment, said it was a chance for people to show their support and offered a moment to reflect on the various conflicts around the world.
Similar events have been taking place across the country and several of them have seen heightened security after recent attacks in Tunisia, France and Kuwait.

24 August 2016 Last updated at 17:01 BST
These are little beads made of plastic that can be found in face scrubs and other cosmetics.
They can cause lots of harm to the environment and wildlife.
Jenny's been finding out more.

Carbon dioxide (CO2) emissions fell 8.9% in 2014 on the previous year, while emissions of all the greenhouse gases were 7.7% below 2013 levels.
The figures come from the Department of Energy and Climate Change (Decc).
The biggest fall in 2014 was in homes (17%), where a warmer year meant less gas was used for heating.
A significant fall was also seen in the power sector (down 13.6%), which saw less use of coal in electricity.

The owl was found on marshes at the former Bettisfield colliery in Bagillt.
RSPCA inspector Jenny Anderton said the bird had no major injuries but was "extremely thin and just needs time to fully recuperate".
The bird is now a rarely seen guest at the Stapeley Grange Wildlife Centre - where just five of the owls have been treated in the last decade.

The Strasbourg judges said Russia had discriminated against three gay rights activists who opposed the law. It was adopted in 2013, banning promotion of homosexuality among people under 18.
The law "reinforced stigma and prejudice and encouraged homophobia", the ruling said.
Gay rights groups condemned the law.
Under the law, private individuals deemed to be promoting "homosexual behaviour among minors" face fines of up to 5,000 roubles (£67; $85), while officials risk paying 10 times that amount. Businesses and schools can be fined up to 500,000 roubles.
Homosexuality was decriminalised in Russia in 1993, but anti-gay prejudice is rife.
Critics see the propaganda law as part of a state campaign to marginalise LGBT activists, whose work includes dissemination of sexual health advice.
The Strasbourg court said the fines imposed on three Russian gay rights activists violated Article 10 (freedom of expression) and Article 14 (prohibition of discrimination) of the European Convention on Human Rights.
According to the court, the legislation aimed at curbing promotion of homosexuality was "not clearly defined" and was implemented in an arbitrary way. It "served no legitimate public interest", the court said.
Russia's justice ministry says it will appeal, arguing that the law is aimed "exclusively at protecting the morals and health of children".
MP Vitaly Milonov, of the ruling United Russia party, who introduced the original bill into the St Petersburg parliament and which formed the basis of the federal law, told BBC Russian that the court's decision was "anti-national".
"It is absolutely harmful, and those who set up this decision are enemies of Europe," he said.
The three activists had been found guilty for protesting against the law in 2009-2012 - outside a secondary school in Ryazan, a children's library in Archangel and an administrative building in St Petersburg.
The court rejected the Russian government's claim that such a law was needed to protect morality.
It found that the government had "failed to demonstrate how freedom of expression on LGBT issues would devalue or otherwise adversely affect actual and existing 'traditional families' or would compromise their future".
Such laws, the judges said, "embodied a predisposed bias on the part of a heterosexual majority against a homosexual minority".
They ordered Russia to pay each of the activists damages of between €8,000 (£7,000; $8,900) and €20,000.
One of the three, Nikolai Alexeyev, hailed the ruling as a "total victory", the BBC's Sarah Rainsford reports from Moscow.
He had picketed a children's library, holding a sign declaring that gay people could also be great - and listing the Russian composer Pyotr Tchaikovsky and filmmaker Sergei Eisenstein as examples.
Thousands of people have marked Armed Forces Day at the National Memorial Arboretum in Staffordshire.
[NEXT_CONCEPT]
Politicians in the UK have said that plastic microbeads should be banned across the world.
[NEXT_CONCEPT]
Greenhouse gas output in the UK fell almost 8% in 2014, although emissions from transport and agriculture rose slightly, official figures show.
[NEXT_CONCEPT]
A "rare" short-eared owl found emaciated in Flintshire is now recuperating well, the RSPCA have said.
[NEXT_CONCEPT]
Russia's "gay propaganda" law is discriminatory and encourages homophobia, the European Court of Human Rights has ruled.