The striking thing about the room fit for a queen is that, well, it doesn't seem fit for a queen. The embroidered silk panel above the bed is the only nod to royal decadence. Otherwise, everything seems rather austere – a few sentimental personal possessions are tucked away amongst a near total lack of frippery. And the narrow single bed seems borderline uncomfortable.
Yet for a long time, this was the Queen's favourite place.
In April 1953, shortly after taking the throne, the Queen launched the Royal Yacht Britannia into the River Clyde. In the next 44 years, it would travel over a million miles, docking in 135 countries and often carrying up to 45 members of the Royal household. It became a floating court, both part of state visit pomp and ceremony and a place of escape for the Royal family. The Queen is on record as saying the Britannia was the one place she could truly relax.
After the Britannia's retirement in 1997, it was refitted to become a tourist attraction and permanently moored in Leith, Edinburgh's port suburb.
At least part of the attraction of going round is seeing how the other half live. But as architect Sir Hugh Casson said: "Simplicity was the key. The overall idea was to give the impression of a country house at sea."
The Queen played an active role in this, turning down the initial designs for the interiors as they were too fussy. The result is a remarkably calm, almost plain floating home – albeit with a grand dining room that could seat 56, where it took three hours to lay out the glass and china with ruler-precision measurements.
But it's the idiosyncrasies that are fascinating. Britannia was the only ship in the Navy where sailors were called by their first name, and shouting was forbidden in order to preserve the tranquillity. The crew developed a special system of hand signals instead.
The sailors didn't wear caps either, which meant they were technically out of uniform and the Royals didn't have to constantly return salutes.
In fact, the crew's quarters are more interesting than those the royals stayed in. The admiral had his own cabin where he would often dine alone, allowing the officers to unwind without the boss looking over them.
Those officers would often hang out in the wardroom anteroom, which was their main recreational space and had a gentleman's club vibe. It also has a stuffed wombat wedged on top of the blades of the ceiling fan.
Apparently, the wombat was given by a lady-in-waiting, and the officers devised a game of "wombat tennis" in which the poor thing would be thrown up to the fan, then batted across the room from wherever it ended up.
As for the Royal Marines band, well they had to double up duties. One ended up as ship's butcher, another sorted out the mail – and they had to find somewhere to practise every day out of royal earshot. And when you see their cramped dorm-style bunks, you realise that the Queen's bedroom isn't quite so spartan after all …
Five more of the Queen's hangouts
Windsor Castle: Lavish state apartments, a sizeable art collection and the unbelievably intricate Queen Mary's Dolls House are amongst the highlights of this Berkshire retreat. See royalcollection.org.uk
Buckingham Palace: The Queen's main residence can only be visited when she's not there – but the state apartments and gardens are open to all from the end of July to late September. See royalcollection.org.uk
Balmoral: Royal summer holidays are generally spent at Balmoral in Scotland. The Duke of Edinburgh's green-fingered inclinations can be seen in the gardens. See balmoralcastle.com
Sandringham: The Queen traditionally spends Christmas at Sandringham in Norfolk, which has an oddly gripping museum of the gifts she has been given while abroad. See sandringhamestate.co.uk.
The Hebrides: When the Britannia was in action, the Queen would take an annual cruise around the remote Scottish islands. Hebridean Island Cruises does much the same now. See hebridean.co.uk.
GETTING THERE Etihad flies to Edinburgh via Abu Dhabi from Sydney and Melbourne. See Etihad.com
TOURING THERE Tickets for the Royal Yacht Britannia cost £14. See royalyachtbritannia.co.uk
STAYING THERE The Malmaison in Leith has doubles for from £65. See malmaison.com
The writer was a guest of Visit Scotland.