Booking a room at a Las Vegas mega-resort should be an easy task: Find out where the client wants to stay and then reserve a room. But a growing mega-resort trend is finding something entirely different than just multiple-room categories. Sometimes these resorts have several different and not widely publicized hotels all within the same complex.

Turns out that operating 3,000 to 4,000 rooms makes it tough to land that five-star designation. But by taking a section of the property and creating suites with upgraded amenities and appointing a dedicated staff helps eschew many of the challenges at running these massive complexes.

Take Wynn Las Vegas for example. When it opened in 2005 the mega resort didn’t just create suites as part of its room assortment, it created a new concept, an entirely separate resort within a resort. Dubbed the Tower Suites, this part of the property is totally isolated from the rest of the hotel. It has its own separate entrance far from the fray, and its own registration desk too.  And with just 296 rooms, there is a heightened service experience. In fact, the rooms at the Tower Suites are rated Five Diamonds from AAA and Five Stars from Mobil. It’s the only casino resort in the world with that dual designation.

By separating a set of rooms from the rest of the property and running it like its own hotel, Las Vegas resorts are better able to serve their most discriminating guests.

Down the Strip, the MGM Grand features Skylofts. These rooms are located on the top two floors of the iconic emerald-hued building and graft an upscale urban aesthetic onto the Las Vegas vibe. And since there are only 51 of these rooms, these multi-level suites have received a five-diamond designation. Guests staying here can expect to ride in a private elevator, enjoy butler service and get chauffeured to and from the airport in a custom Maybach 62 limousine where guests are greeted by a personal concierge.

There are many new projects currently rising on the Strip. And as they open expect more properties to feature these entirely unique and somewhat secret hotels.