(CNN) — With the growing popularity of Airbnb and boutique hotels, large international hotel chains have had to work harder than ever to win travelers' loyalty. Now, more than ever, high-end luxury chains such as The Four Seasons and St. Regis are endeavoring to banish brand-name boredom.
Even mid-market chains have stepped up their game with newly revamped properties to prove to travelers there's strength in numbers. We've handpicked the most luxurious properties offered by the world's top hotel chains:
St. Regis: St. Regis Princeville Resort (Kauai, Hawaii)
Along with The Luxury Collection, St. Regis is the premier luxury brand of Starwood Hotels and Resorts, one of the world's largest hotel groups. Though all 57 St. Regis-branded properties are unfailingly luxurious, its sole Hawaiian property -- on the island of Kauai -- stands above the rest.
For one, there's its show-stopping setting: the hotel balances dramatically on a cliff on the island's lush North Shore.
Taking advantage of its spectacular backdrop, the hotel's 169 rooms and suites boast expansive terraces that overlook Hanalei Bay and Makana Mountain.
Not that you'll spend much time indoors -- the St. Regis Princeville is home to a 5,000-square-foot oceanfront infinity pool and one of Hawaii's best beach bars.
Standout feature: Its 10,000-square-foot Halele'a Spa is one of the best (and largest) spas in Hawaii, with specialty treatments that incorporate Kauai's indigenous fruit and flowers.
Four Seasons: Four Seasons Hotel Firenze (Florence, Italy)
Four Seasons Florence: Unabashed opulence.
Four Seasons Firenze
The Four Seasons lays claim to some of the most legendary and luxurious hotels in the world. But of its 98 five-star properties across the globe, the hotel group's crowning jewel is the Four Seasons Hotel in Florence, Italy.
The magnificent property consists of not one but two Renaissance palazzi: the 15th-century Palazzo della Gherardesca and the 16th-century La Villa, a former convent. Its 116 rooms and suites are divided between the palazzi and decorated lavishly with frescoes, friezes, antiques and crystal chandeliers.
At the center of it all, there's a sprawling outdoor pool, hot tub, greenhouse and 8,500-square-foot spa.
Standout feature: The property is home to Giardino della Gherardesca, Florence's largest private garden -- 11 acres of manicured lawns, flower gardens and centuries-old forests, dotted with original statues and fountains.
The Peninsula: The Peninsula Paris (Paris)
The Hong Kong-based luxury hotel group might be best known for its five-star properties throughout Asia. But interestingly, its most lavish property is in France. The Peninsula Paris -- the group's first European property -- took four years and $850 million to construct.
Built on the former site of the Hotel Majestic, where George Gershwin penned "An American in Paris" in 1928, the 19th-century building was painstakingly restored to its former splendor. The facade features original bas-reliefs and sculpted stonework, while the palatial interiors glisten with marble, mosaics and individually painted gold leaves (40,000 in total).
There are 200 rooms, a 19,000-square-foot spa and an indoor swimming pool.
Standout feature: The hotel's piece de resistance is its rooftop restaurant, L'Oiseau Blanc, which offers 360-degree views over Paris.
Ritz-Carlton: The Ritz-Carlton Tokyo (Tokyo)
Ritz-Carlton Tokyo: 12 swish stories.
All 87 Ritz-Carlton hotels and resorts -- scattered across 29 countries -- are renowned for opulence and elegance. But its most high-end property is in Tokyo, in the heart of the Roppongi district.
The Ritz-Carlton Tokyo occupies 12 floors of the 53-story Midtown Tower, Tokyo's tallest skyscraper -- meaning each of its 245 guest rooms have unrivaled views over the Tokyo skyline and Mount Fuji.
Views aside, the hotel has sleek, ultramodern interiors and contemporary artwork. Hotel highlights include a Michelin-starred restaurant, a 22,000-square-foot spa and a wedding chapel.
Standout feature: Its 45th-floor Sky Lobby, with its sweeping city views, makes for an unbeatable, dramatic entrance -- particularly after sunset.
InterContinental: InterContinental Danang Sun Peninsula Resort (Son Tra Peninsula, Vietnam)
Established more than 70 years ago, InterContinental is renowned for being the world's first international luxury hotel brand. Today, the InterContinental Hotel Group consists of eight different brands -- including Kimpton Hotels and Crowne Plaza -- and has more than 4,800 properties across 100 countries.
Though the hotel group has a wealth of high-end properties in almost every major city, its most luxurious hotel is located in the hills of the Son Tra Peninsula in Vietnam. The temple-inspired InterContinental Danang Sun Peninsula was designed by celebrated architect Bill Bensley to blend into its dramatic mountainous setting.
More than 180 spacious guest rooms are decked out in local merawan wood, custom-made tiles and plush, embroidered silks. Penthouses and villas have multiple al fresco areas and private plunge pools overlooking the ocean.
It's not just looks: the property is also home to an award-winning spa and a restaurant helmed by three Michelin-starred chef Pierre Gagnaire.
Standout feature: The half-mile-long stretch of pristine, private beachfront tucked beneath the property, accessible via cable car that runs down the mountain.
Mandarin Oriental: Mandarin Oriental, Hong Kong (Hong Kong)
Mandarin Oriental Hong Kong: Now with added restaurants.
Mandarin Oriental Hong Kong
Though the Mandarin Oriental Hotel Group currently operates 41 hotels in 27 countries, its most upscale offering remains its flagship hotel in Hong Kong.
Built in 1963, the Mandarin Oriental, Hong Kong was quickly named one of the world's greatest hotels by Fortune magazine -- a title it's worked hard to keep. In 2005, the property underwent a year-long, $150 million hotelwide renovation.
All 501 guest rooms were decorated with walnut paneling, rich silk drapes, contemporary furnishings and high-tech amenities. Its food-and-beverage program was revamped with a whopping 10 new restaurants, including the two Michelin-starred Pierre and one-Michelin-starred Mandarin Grill.
Standout feature: Its 23,000-square-foot spa, which spans three stories and features an ice fountain, hydrotherapy circuit, Chinese herb steam room and tea lounge.
Hilton: Hilton Barra Rio de Janeiro (Rio de Janeiro)
With more than 540 upscale properties across 78 countries on six continents, it's no wonder that the Hilton is the most sought-after luxury hotel brand in the world. The hotel giant's newest property, which opened just last year in Rio's Barra neighborhood, takes the crown thanks to its high glamor and show-stopping contemporary design.
Upon entrance, guests are wowed by a vast lobby with 120-foot-high ceilings that, when illuminated, act as an enormous glass box shining light throughout the property.
Public areas are decorated with colorful art by Brazilian artists like Iole de Freitas, Hugo Franca and Roberto Burle Marx, giving the hotel a museum-like feel. Its 298 guest rooms are some of the largest and most stylish in the city with modern furnishings and custom-designed beds. Complimentary Havaianas flip flops in every room are a nice touch.
Standout feature: The hotel's rooftop infinity pool, with its magnificent view of the lagoons and Barra da Tijuca mountains, is the best spot in Rio to watch the sunset.
Hyatt: Park Hyatt New York (New York)
Park Hyatt New York: How do you get to Carnegie Hall? Cross the street.
Park Hyatt New York
Not only is the Park Hyatt New York the most luxurious property in the Hyatt Hotels Corporation portfolio, it's hands down one of the best hotels in New York City.
Covered in cascading glass panels, the $400 million hotel -- opened in 2014 -- was designed by Pritzker Prize-winning architect Christian de Portzamparc. Upon entrance, guests are greeted in the ultramodern lobby by iPad-armed staff clad in Narciso Rodriguez-designed uniforms.
Its 210 guest rooms are the largest in the city -- averaging 530 square feet -- and feature sweeping views of the Manhattan skyline and Central Park. The property is located directly across the street from Carnegie Hall and just one block from Central Park, making it one of the most coveted addresses in town.
Standout feature: The three-story Spa Nalai is arguably the best spa in the city, with a spa terrace, eucalyptus steam room and a 65-foot swimming pool with underwater speakers that stream music from Carnegie Hall.
Sheraton: Sheraton Grand Hotel Dubai (Dubai)
Though it's the flagship brand of Starwood Hotels and Resorts, Sheraton hotels are often overlooked by high-end luxury travelers in favor of St. Regis-branded properties. That doesn't mean that certain Sheraton hotels aren't just as upscale.
In fact, the hotel giant recently re-branded 27 of its properties as Sheraton Grand Hotels in order to better distinguish its top-tier luxury hotels. It's a smart move, considering there are a whopping 525 Sheraton-branded hotels to date.
Not surprisingly, the ritziest of the lot is located in Dubai, on the skyscraper-studded Sheikh Zayed Road. Blending in with its neighbors, the hotel stands at 54 stories high, and has a whopping 654 rooms, including 56 suites and two Presidential Suites. There's also a two-story ballroom and a 5,000-square-foot spa -- one of the largest in Dubai -- located on the hotel's 52nd floor.
Naturally, the hotel's interiors are dominated by gold tones and glossy Carrara marble, accented by plush leather furnishings and flashy, ultramodern light fixtures.
Standout feature: The open-air rooftop swimming pool with unmatched views of the Dubai skyline.
Marriott: JW Marriott Venice (Venice, Italy)
JW Marriott Venice: Seaside resort or city hotel?
JW Marriott Venice
The latest addition to the Marriott portfolio is proof that five-star luxury doesn't have to come with a five-star price tag.
Like the 75 other JW Marriott-branded hotels -- separate from the larger Marriott hotel chain, which operates more than 500 hotels -- the newly opened JW Marriott Venice offers reasonable rates without skimping on quality, service and amenities.
For starters, the sprawling property is set on its own private island on the Venetian lagoon -- a haven of tranquility away from the bustling tourist crowds. In fact, it feels more like a seaside resort than a city hotel, thanks to its waterfront appeal and abundance of lush, leafy gardens.
Rooms and suites are outfitted with private lagoon-facing balconies, and feature a refreshingly clean, modern aesthetic rarely seen in Venice. Also a rarity in Venice: its sprawling rooftop pool with panoramic views over Venice and the lagoon.
Standout feature: The stand-alone, two-level Villa Rosa is set in its own private garden with a plunge pool overlooking the Venetian skyline.