At luxury hotels in Washington, making international guests feel at home sometimes involves the use of heavy machinery.

A few years ago, the Fairmont Hotel overhauled an entire bathroom to accommodate a British visitor’s special-order hot tub. The Ritz-Carlton routinely installs bidets for Middle Eastern travelers. And at the Willard Hotel, there have been requests to put thrones in guest rooms.

“Every year or two, we’ll have someone send in a mattress before they arrive,” said Suzie Sims, director of diplomatic sales for the Ritz-Carlton. “Sometimes they’ll send in furniture and ask us to recreate the personal spaces in their homes on the other side of the world.”

It’s no secret that international visitors and diplomatic delegations are a large source of revenue for Washington’s hospitality industry. Last year, foreign travelers accounted for 10 percent of the District’s visitors, but 27 percent of tourism spending, according to the marketing organization Destination D.C.

The number of international travelers in the area has been rising steadily in recent years, up 31 percent since 2000 and totaling 1.8 million people in 2011, a bright spot in an otherwise sluggish domestic economy — and hotels are increasingly going to great lengths to make sure their clients feel right at home.

“Since Washington is so international, our clients come from all over the world and we want to make them feel comfortable,” said Liliana Baldassari, a spokeswoman for the Four Seasons in Georgetown. “Any guest can ask for anything, and we’ll have it for them.”

Muslim guests at the hotel are likely to find prayer rugs, a compass and Koran in their bedrooms. For Japanese travelers, kimonos and tea pots take the place of standard bathrobes and coffee makers. And for other international visitors, there are personalized newspapers and satellite news stations from their home country waiting for them.

“You find out what makes the guests happy,” said Mark Andrew, general manager of the Fairmont in Washington. “And then you exceed their expectations.”

Even Donald Trump is hoping to tap into the area’s large concentration of monied visitors. Earlier this year, he secured rights to redevelop the Old Post Office Pavilion in downtown Washington with plans to turn it into a luxury hotel, complete with the sort of oversized suites that have proven popular with diplomatic missions and foreign guests.

“There isn’t any group that is more sought-after by hotels,” said Vivian Deuschl, an industry expert. “They have a lot of money and they’re willing to spend it.”

Visitors from China

Last year in Washington, there were more visitors from China than from any other country. Hotels have taken note.

The Sofitel in Northwest Washington recently created a Chinese business travelers’ program to accommodate the influx of Asian tourists. The hotel’s staff has received training on Chinese customs, and hotel televisions now broadcast Phoenix InfoNews, a 24-hour, Hong Kong-based news channel.

“Sometimes we set out bowls of oranges and tangerines because they’re a sign of wealth and good luck,” said Pierre-Louis Renou, general manager of the Sofitel. “We have so many Chinese travelers that we started getting China Daily News every Monday to Friday.”

The Hay-Adams has begun welcoming Chinese guests with bowls of hot noodles. The hotel is also in talks to begin offering a high-end luxury magazine in Mandarin in its guest rooms.

“Expectations are becoming so high that nothing seems that outrageous anymore,” said Sarah Deam, director of marketing and sales for the Hay-Adams.

More travelers, more needs to meet

The first international delegation arrived at the Willard in 1860, when 70 Samurai princes from Japan stayed at the hotel for a month. The Willard refurnished 60 rooms for the delegation, adding new red carpeting and creating three dining rooms and a ladies’ tea room to be used exclusively by the Japanese guests.

Not much has changed since then, said Barbara Bahny, a spokeswoman for the hotel.

“Of course we still do all of those things,” she said.

The one aspect that continues to evolve, though, is the type of international travelers coming to Washington. As world economies change and travel becomes more accessible, area hotels say they are seeing more and more guests from all over the world.

“Traditionally, there was only one group of foreign visitors that anybody paid attention to, and that was the Japanese,” Deuschl said. “Ten or 15 years ago, a new market emerged — Russian travelers, Middle Eastern visitors with a lot of money. And all of a sudden, you needed a prayer rug, you needed to adjust your menu, you needed to make sure someone on staff spoke all these different languages.”

Even so, hotels say they walk a fine line between being culturally savvy and overbearing.

“You have to be very sensitive,” said Timothy Harleth of the Mandarin Oriental in Southwest Washington. “A lot of times Middle Eastern clients just want to come in and have a steak — not necessarily the same thing they eat back home.”

Personal service

At most hotels, preparations begin when guests make their reservations. Employees try to get a sense of the client’s preferences — everything from what kind of food they like to whether they’d prefer monogrammed towels. For the most frequent clients, there are often databases of preferences that hotel employees can quickly reference for each stay.

“It’s really all about personalized service,” said Ernie Arias, director of sales and marketing for the Park Hyatt. “We try to find out right away what their preferences are, what foods they like.”

Amenities such as foreign news are also popular. Many hotels say they have a system that allows them to immediately print out daily newspapers from around the world. Hotels such as the Ritz-Carlton and Mandarin Oriental now have employees dedicated to overseeing international and diplomatic travelers.

Some specific needs are met on request — removing alcohol from minibars for Muslim guests, for example, or creating “blackout” rooms where all windows are covered so jet-lagged guests can sleep in complete darkness.

“When you come to a hotel, you want to get a good night’s sleep — even if that’s in your own time zone,” said Andrew of the Fairmont. “Jet lag could be very costly for some of our guests, so we’ll serve dinner for breakfast and breakfast for dinner to fit their [internal] clocks.”

Last year, the Fairmont prepared for a Belgian prince’s stay by printing out photos of his family. The hotel staff framed the photos and spread them out throughout the guest’s room.

“You’re staying here for a while, so why not have pictures up and make it feel like home,” Andrew said.