World's Tallest Tower Rises in Tokyo

Guinness World Records certified the Tokyo Sky Tree as the tallest tower in the world this month.

Rising like a space age Eiffel Tower on growth hormones, the newly built Tokyo Sky Tree won't officially open its elevator doors until May 2012.

Yet the 2,080-foot-tall (634-meter-tall) structure has already built a lofty reputation. Under construction since 2008, Japan's latest landmark was this month certified the world's tallest tower by Guinness World Records.

But hold on, what about Dubai's Burj Khalifa? Completed in 2010, the giant skyscraper measures 2,723 feet (830 meters) tall.

Yes, say the records people, but the Burj Khalifa is the world's tallest building.

Tokyo's Sky Tree is a tower, the difference being "that less than 50 percent of the construction is usable floor space," explained Guinness World Records spokesperson Anne-Lise Rouse.

By that definition, the Tokyo Sky Tree topples the record of the 1,969-foot (600-meter) Canton Tower in China's Guangdong Province. And the new record-holder presently has no known challengers, Rouse said.

Towering Tourism Boost for Japan?

Triangular at its base, the world's tallest tower morphs into a tubular design as the latticed-steel structure rises. The Sky Tree's main role is to serve as a television and radio broadcasting mast.

But the Sky Tree is also set to become a major visitor attraction, and a well-timed pick-me-up for Japanese tourism after the devastating earthquake and tsunami that struck the country in March 2011.

(See pictures: Japanese tsunami and before and after satellite images)

There are two observation decks, at 1,148 feet (350 meters) and 1,476 feet (450 meters), with admission tickets set to cost 2,000 yen (U.S. $26) and 3,000 yen ($39) respectively. The upper deck includes a glass-covered "sky walkway," where sightseers can stroll around the tower for a 360-degree view of the world's most populous city.

Given Tokyo's seismically active location, the Sky Tree may raise a few eyebrows. But the towering structure is reportedly built to withstand an 8.0-magnitude earthquake.

Sky Tree's designers, Nikken Sekkei, highlight antiquake architectural features, including a vibration-control system that employs a central spine of reinforced concrete pillars.

Quake Proof?

Based on traditional antiquake technology found in the construction of Japanese pagodas, the central column counteracts the sway of the tower's outer shell during earth tremors.

Andrew Charleson, an earthquake engineering expert at Victoria University of Wellington in New Zealand, said in an email that such damping devices "will be particularly effective in reducing the vibrations due to wind gusts and could also reduce earthquake movements."

"I would expect the tower to be safe in a large quake," he added. "Because it is so high and slender, it will vibrate very slowly during an earthquake.

"This slow vibration-say six seconds for one cycle-will be at such a different frequency from an earthquake," Charleson said.

In other words, the only real threat to visitors to the Tokyo Sky Tree is probably going to be vertigo.