So what do Arlington and Las Vegas have in common, you ask?

Why, an ultra-luxury condo tower being built by South Florida developer Turnberry Ltd., of course.

Never heard of Turnberry? You're probably not traveling in the right circles. Think Miami condos, the Fairmont Turnberry Isle Resort & Club and Aventura Mall in South Florida, a planned redevelopment of the iconic Fontainebleau Hotel in Miami Beach, an earlier Vegas condo project that was the first on the Strip, a joint Vegas hotel-condo venture to connect to the MGM Grand casino, and resorts in the Bahamas and Orlando.

There are some differences, though, as you might expect, between what's happening in Sin City and right here in Rosslyn.

At Turnberry Towers Las Vegas, the dual 45-story towers are a three-minute walk from the Strip. The apartments cost from $500,000 to more than $1.3 million. The project is right across the street from the company's first ultra-expensive Vegas project, Turnberry Place -- and from the showgirls at the Sahara.

Turnberry Tower Arlington, to be built on the site of what's now a Best Western hotel near Key Bridge, will be just 26 stories. But that's enough to qualify it as the tallest condo building in Rosslyn or Arlington and maybe even in the region, according to Turnberry and Arlington County planners who approved the tower by different names in 2001 and 2004.

The high-rise at 1881 N. Nash St., scheduled to be finished in the spring of '08, will have 247 units, ranging in size from 1,312 square feet for one bedroom and 1 1/2 baths to 5,304 square feet for the tower suite -- three bedrooms, a formal dining room, a library, a lounge, a staff suite and 5 1/2 baths.

The units here are pricier than in Vegas. They range from $800,000 to a little more than $6 million for the penthouse, according to Jim Cohen, vice president of sales and marketing of Turnberry Ltd. in Miami.

Turnberry Tower Arlington won't have access to casinos; the 176-room Best Western sits next door to a Holiday Inn. But it will have those Rosslyn views of Georgetown, the monuments and the Potomac.

And it will have amenities including private elevators, a spa and fitness center, an indoor swimming pool, Italian cabinets, Miele appliances, Jacuzzi tubs, and floor-to-ceiling windows. Plus, it will be "green" building certified, for environmentalists with a lot of green.

But aren't both ventures big gambles in two overheated condo markets?

After all, Arlington and Fairfax counties have 14,000 condo units under construction and 28,000 more planned or proposed, but only 4,000 units there sold last year, according to Kenneth Wenhold, director of the Virginia-Maryland division of MetroStudy, a Houston-based market research firm.

And in Las Vegas, where some had estimated last November that as many as 50 towers were being built or planned, the climate appears to have become way too cool lately, leading several developers to pull the plug. Among those leaving: Ivana Trump, ex-wife of Donald, who apparently doesn't vanna build her Ivana Las Vegas anymore, and Related Cos., which took 500 luxury units off the market in January.

Turnberry, however, sees no problem in either market, Cohen said.

Before deciding to enter the Washington region about a year and a half ago, "we watched that market," he said. "And it really had a good feeling as an area of need for luxury. We specialize in luxury, that's the basis of the whole business."

Since a sales office opened in the back of the Best Western about five months ago, about 120 condos have sold, including a $4 million unit, he said.

The experts can be wrong on such things, Cohen added.

"All the experts said not to go into condos in Las Vegas" because tourists wouldn't desert the hotels for their own luxury suites, "but we went against all the experts and had tremendous success."

Vegas still is "very strong" for developers who are careful, he explained. And that means catering to buyers who will live in the buildings, not those who are simply making a speculative investment. "We didn't jump on the investor market. We take a 30 percent deposit on a condo . . . and that takes away a lot of the investors," Cohen said.

In the Washington area, "we know that the investor market has dried up quite a bit," he said. "But our sales pace is just as we estimated it going in."

The project "has wonderful amenities" and "the model looks great," said Ann Worley, an agent with McEnearney Associates in McLean, who had clients who considered buying there. She noted that the tower has lots of competition at the high end, in Rosslyn and Georgetown. Her clients, who were in their seventies, decided not to buy because "it will take three years to build" and because "the best views are already gone."

Turnberry is partnering on the project with Facchina Development Co. of La Plata. The luxury tower was originally approved in mid-2001 as an even more swank building, with only about 176 units and a different developer. But the plan was suspended after Sept. 11, 2001, and re-approved with a different name and more units in 2004.