LAS VEGAS - Adding 928 rooms and suites to the Bellagio entails more than just building a 33-story tower. With Bellagio recognized by AAA as a five-diamond property -- the organization's highest rating -- the hotel-casino's executives say they needed to carry that same level of expectation into the resort's newest addition, which opens to customers this morning.

The $375 million Spa Tower expansion also includes a new upscale restaurant, four specialty retail shops, 70,000 additional square feet of meeting space, and a large renovation to the property's spa and salon component. Also, MGM Mirage, Bellagio's parent company, spent an additional $110 million to refurbish the property's existing rooms and suites so they would match offerings in the new tower.

"We needed to create an environment for our guests where if someone were to ask to be placed in one of the new hotel rooms, it wouldn't matter where in the hotel they were located," Randy Morton, Bellagio's vice president of hotel operations, said Wednesday during a tour of the expansion. "The idea is that all of our hotel rooms, regardless of which tower you might be staying, are newly decorated and have all the amenities one expects from this property."

Bellagio's expansion, the property's first since its 1999 opening, did not add any casino space. Morton said the current gaming configuration of 125,000 square feet was sufficient to meet the Bellagio's needs.

Hotel executives and employees spent the past few nights in Spa Tower rooms, serving as quality control before guests arrive.

The Spa Tower, southwest of the resort's conservatory gardens, encompasses 819 guest rooms and 109 suites on the top seven floors, including two 4,500 square foot presidential suites that Morton said rent for $5,000 per night.

Bellagio's average room rate is $250 per night and Morton added the property is sold out this weekend and through the New Year's Eve holiday, where the average rate is $599 per night. He estimated the expansion said the property added 1,100 full-time workers and 300 part-time workers to give the resort a total of 10,000 employees.

In addition to the rooms and suites, a significant part of the expansion focused on the property's spa and salon. The resort doubled the size of the spa to 55,000 square feet, adding increased workout space, a renovated reception area, and increased the number of massage and therapy rooms while upgrading the facility's offerings. The salon grew to 10,000 square feet and now has 61 stations for hair, makeup and beauty treatments.

Cost to use the workout facility is still $25 a day for guests and additional offerings, such as massages, body care and unique world therapies have various prices ranging up to several hundreds of dollars per session.

"Some of the treatments offered at the spa are not found anywhere else on the Strip," Morton said. "A facility such as this is a source of revenue for the Bellagio and it's an aspect of the property our customers come to expect."

Morton said the Bellagio spa earns a profit of 35 percent above similar facilities.

The new restaurant, Sensi, offers a diverse menu with tables surrounding the kitchen that doubles as a "culinary theater." Shopping offered along the Spa Tower's walkway include Regali, an upscale men's store; a remodeled garden center; a Bellagio logo shop; and a newsstand. A high-end pastry shop is still under construction. The expanded convention area gives Bellagio a total of 200,000 square feet of meeting space with three large ballrooms, sized 45,000 square feet, 35,000 square feet, and 25,000 square feet.

Increasing the convention space allows the resort to focus on gatherings of difference sizes, such as corporate meetings. Future convention bookings are up 35 percent overall, Morton said. One specialty room in the new convention area is dedicated as an exhibition kitchen where celebrity chefs can entertain and offer cooking demonstrations for up to 60 guests. The room can also be rented out for group activities in association with a meeting or convention.