These might well be the absolute biggest in the world, but why risk offending some giant left off the list?
1. Izmailvo Gamma-Delta Hotel, Moscow: 7,500 rooms. This gargantuan property, built in 1979 during the waning days of the Soviet empire, can hold up to 10,000 visitors at a time -- which, for reference purposes, equals a smallish-size group from the Unemployed Journalists Union (forgive the in-joke).
2. The Venetian, Las Vegas: 7,117 rooms. The real Venice is a scale model of this.
3. First World Hotel Genting Highlands Resort, Genting Highlands, Malaysia: 6,118 rooms. Perched on a peak of the Titiwangsa Mountains (an hour's drive from Kuala Lumpur), this expansive property boasts that "All rooms are equipped with fans."
4. MGM Grand Las Vegas: 5,044 rooms. With every conceivable type of game in the casino, you'll run out of money way before the hotel runs out of rooms.
5. Wynn Las Vegas/Encore: a combined 4,734 rooms. You can get married here, live here and, given the dimensions of the place, organize a sizable state militia here.
6. Luxor Las Vegas: 4,408 rooms. Carrot Top is a big draw in the nightclub, and there's plenty of room for the rest of the vegetable section, too.
7. Mandalay Bay/THEhotel, Las Vegas: a combined 4,332 rooms. As if mighty Mandalay Bay wasn't impressive enough, they go add a property-within-the-property so notable, even the "The" in its name demands genuflection.
8. Ambassador City Jomtien, Pattaya, Thailand: 4,219 rooms. With more than 50 meeting rooms and a giant reception hall able to host up to 5,000 people, this is a perfect fit for the Association of People Who Claim They Were at Woodstock.
9. Excalibur Hotel and Casino, Las Vegas: 4,008 rooms. Complete with its own castle, the Excalibur is big enough to host the world series of jousting.
10.Aria Resort & Casino, Las Vegas: 4,004 rooms. The smallest property on our list still could apply for its own zip code, if it wanted to.
Source: Meetings & Conventions