A heart-pounding attraction atop Japan's tallest building — where visitors can stroll along a narrow outdoor observation corridor overlooking Osaka — was unveiled to the press Wednesday, a week ahead of its official opening.

"Edge the Harukas," located on the roof of the 60-story, 300-meter-high Abeno Harukas building, provides a sky-high view for those brave enough to traverse the 20-meter-long ledge while tethered to the building.

Accompanying staff will take photos of visitors against the backdrop of the city's skyline.

Height restrictions apply, with 146 cm being the minimum and 199 cm the maximum.

The attraction costs ¥1,000 ($9.30) per person, in addition to the observatory's ¥1,500 admission fee per adult.

On Wednesday building operator Kintetsu Real Estate Co. invited some university students for a trial run.

"I enjoyed the incredible openness in the absence of windows," 20-year-old Hannan University student Yuri Kawaguchi said after braving the open-air observation platform.