The secret, ultra-private rooms luxury hotels don't tell you about

The 50th-floor Suite 5000 at the Mandarin Oriental in New York is so exclusive it isn't even listed on the hotel's website. Photo / Supplied.

When booking a stay at a hotel, travellers might think they can have their pick of any room, but it's not always the case - because some hotels have secret ultra-swanky rooms they don't advertise.

The reason? No doubt they are there as an option for VIPs who want to feel that they're getting something extra special and want total privacy (some come with their own entrances).

Of course, secret luxury doesn't come cheap. The Mandarin Oriental New York has one that costs $36,000 (NZ$53,066) a night and the newly-opened Blue Lagoon Retreat in Iceland charges $10,500 (NZ$15,500) for its secret no-pictures-available room.

According to Bloomberg, it is triple the size of any suite in the property and boasts a private entrance, private balcony as well as a private bathing area within the Blue Lagoon.

It is also spread across two levels and also features a kitchen, dining room, bedroom with walk-in wardrobe as well as a steam bath and sauna.

But it is not just about giving guests privacy. Stephen Brandman, who runs management firm Journal Hotels, told the website that hotels also want to protect their most expensive rooms.

Holidaymakers wanting to stay at the $45,000-per-night Hilltop Villa at Laucala Island Resort in Fiji have to apply or be invited. Photo / Supplied

He explained: "You don't want 10 people coming together and each throwing in $200 so they can have a big party. Think about it. A load of high school prom students rent a penthouse, and all of a sudden you've got a big problem."

New York hospitality professor Bjorn Hanson added: "Rooms that have something fragile about them - the art, a Steinway grand piano - where there's too much risk of wear and tear will be held back. They won't be available to the public but assigned to VIPs."

This could be the reason why the Mandarin Oriental, New York doesn't advertise its 50th-floor Suite 5000.

The stylish pad boasts a library of films and music curated by Academy Records - and the walls are adorned with artistic portraits and sculptures.

Moving through the 3,300-square-foot apartment, there are three bedrooms, a living room and dining space to seat 10 people with a twinkling Swarovski wall installation to set the tone.

The stunning Blue Lagoon Retreat hotel in Iceland is built on the country's famous geothermal waters. Photo / Supplied

Somwhere around here: The Blue Lagoon hotel has a $10,500-per-night room that is not listed on the hotel's website, neither is there any description or any pictures. Photo/Supplied

Other incredible secret hotel rooms include the NZ$66,000-per-night Hilltop Villa at Laucala Island Resort in Fiji, which you have to apply to book or be invited to stay at, the 21 Boulevard penthouses at The Cosmopolitan in Las Vegas - the hotel management decides which casino high rollers should be allowed to stay in them - and the penthouse at the JW Marriott Essex House in New York.

At JW Marriott Essex House in New York, hotel management decides who should stay in the most exclusive suites. Photo / George Rose,Getty