It was 11 am behind the crenellated walls of one of England’s best-known attractions, and I was in a room few people know exists: an all-but-secret pub that’s off-limits to the public. Since it was first built in 1078, the Tower of London has been a royal palace, imposing fortress, infamous prison and favoured execution site.

It’s also a great spot for a drink. If, that is, you happen to be a Yeoman Warder.

Commonly known as Beefeaters, the elaborately uniformed Yeomen were introduced in 1485 by Henry VII to help guard the Tower – then a cobbled complex where not only prisoners and princes, but also hundreds of residents, lived. The Yeomen have since become the iconic, much-photographed public face of one of the UK’s most-visited sites, one that drew more than 3 million visitors in 2014 alone.

But since the Tower’s current 37 Yeomen are kept busy leading guided tours and meeting selfie-craving tourists – alongside ceremonial duties that have changed little over the centuries – a cosy bolt hole for an end-of-shift tipple is essential.

May you never die a Yeoman Warder

“There were dozens of inns and bars in the Tower during the 18th and 19th Centuries, but this is the last one,” Chief Yeoman Warder Alan Kingshott told me. We were inside the pub, called the Yeoman Warders Club, where drinks include Beefeater Gin (of course) and Beefeater Bitter made for the Yeomen by UK brewery Marston’s. It’s not open to the public. But invited guests – like myself – are allowed.

With red banquettes and dark wood tables, the watering hole feels like a country pub fused with a members-only bar. But the décor is unique. There’s a ceremonial axe in one corner; photos of guests like Bruce Willis and Tom Clancy in another; and even a framed Rudolf Hess signature on official Tower of London stationery. The captured Nazi was briefly imprisoned in the Tower in 1941, and during his four-day stay he signed autographs for several of the Yeomen he came into contact with.

But it’s the pub’s direct connections to the Yeomen themselves that are most intriguing. Dozens of wall-mounted plaques represent the regiments each Yeoman has come from – new applicants must have honourable armed forces records going back for at least 22 years before being considered.

Meanwhile, a row of silver tankards recalls a Beefeater ceremony few outsiders know about. “We each have a tankard, and we swear in new recruits around a large bowl of port,” said Kingshott. “They swear allegiance and we toast them with the line: ‘May you never die a Yeoman Warder.’”

It sounds like an odd salute, but like everything Tower-related, there’s a story behind it. Historically, Yeoman jobs – which included room and board (the Beefeater nickname reputedly comes from a time when they were partly paid in beef) – were sold to the highest bidder. Appointees could retire and sell the position on whenever they wanted. By passing away in office, you lost this lucrative payday, meaning that dying as a Yeoman was unlucky.

“We still use the toast but everything changed here in 1826,” said Kingshott. “That’s when the Duke of Wellington decided all Yeomen had to be ex-soldiers appointed for their distinguished military service – and the buying and selling of positions was stopped.”

Today’s Yeomen still have living quarters in the Tower – typically apartments built into the Tower’s old walls (Kingshott’s is at the top of a 48-step spiral staircase) – but they now pay a reasonable rent. And, according to Kingshott, most also maintain homes outside where they can have a break from their Beefeater jobs.

Their roles also have changed: instead of being prison guards and protectors of the crown jewels, the Beefeaters are more about greeting and guiding. “Most of our remit has been front-of-house since the Victorian era,” said Kingshott. Alongside excellent service records and the ability to uphold the traditions and dignity of the post, candidates must be perfectly suited to dealing with the public.

While meeting international visitors is exciting, “being asked to have your photo taken the moment you leave your accommodation is harder to get used to,” said the Tower’s newest Yeoman Warder, Spike Abbott, appointed in April 2015.

Yeomen receive bottles of Beefeater gin on their birthdays

Changes aside, the Beefeaters still retain many old traditions. Some of them are quirky: an old agreement with Marston’s for use of the Beefeater image means that Yeomen receive bottles of Beefeater gin on their birthdays, for example. Others have more gravitas, including their part in the Ceremony of the Keys, which takes place when the Tower is locked up every night, a ritual stretching back 700 years.

There’s also the Ravenmaster, a traditional Yeoman Warder post currently held by Chris Skaife. The Tower’s resident black-hued corvids are almost as iconic as the Beefeaters, so it’s a serious responsibility.

“No one knows when the ravens first came here,” Skaife said. “But legend says if they ever leave, the Tower and the kingdom will fall. That’s why Charles II decreed there must always be at least six of them here.” The current seven residents have names including Merlin, Rocky and Jubilee. (Read more about the ravens on our sister site BBC Culture).

As Ravenmaster, Skaife’s job involves cleaning birdcages, putting his charges to bed and ensuring they’re well fed. “I pick up raw meat from Smithfield Market and give the birds a variety every day,” he said. “Once a week they also enjoy an egg – plus occasional rabbits, which I feed to them whole because the fur is good for them.”

Ravenmaster isn’t the only behind-the-scenes job. Yeoman Clerk Philip Wilson has been at the Tower for 18 years, making him the longest-serving current Beefeater. And while he’s officially responsible for Ceremony of the Keys administration, he also ensures each Yeoman is perfectly attired. “It’s not a traditional part of the Clerk’s position, but it’s a role I’ve taken over because I used to be Master Tailor of the Coldstream Guards,” said Wilson.

All new Yeomen are measured and fitted for their bespoke outfits. “The Tudor state dress – the ‘red and gilt’ uniform we’ve worn since 1549 – has changed very little. But the blue and red ‘undress uniform’, our daily outfit, wasn’t introduced until 1858,” Wilson said. Today, the Tudor state dress is only worn when Yeomen are attending state occasions – or when the monarch visits the Tower.

Bartending, though, may be the most surprising Yeomen job of all. Tucked into the Tower’s southern wall – a short walk along the cobbles from Traitor’s Gate – the private pub, about the size of a tennis court, is open from 8:30 pm Monday to Saturday.

The exact date of when the Yeoman Warders Club was founded isn’t known; it has occupied several sites at the Tower over the centuries and has been in its current location for more than 60 years. The Yeomen take turns manning the bar here and they have to pay for their drinks; prices are not subsidised.

While maintaining a work-life balance is a challenge for most Beefeaters, thanks to being constantly on duty (and to spending so much off-duty time living in their place of work), for 63-year-old Kingshott, the job’s uniqueness makes up for it.

“There’s really nothing like it and it’s been an absolute privilege to have this role. But I don’t want to overstay my welcome,” he said, glancing skyward over the lofty old walls – in just the way every Chief Yeoman Warder in history must have.

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