An incline was built into the upper observation deck of Tokyo Skytree to give visitors a thrill and make the experience more memorable, according to one of the architects who designed the capital's newest landmark.

Visitors to the tower, which opened Tuesday in Sumida Ward, access the 450-meter-high Tembo Galleria by elevator but have to ascend the final 5 meters through a glass-covered spiral Sky Walk.

"I wanted people to feel a sense of accomplishment by climbing the last section on their own," said Tetsuo Tsuchiya, one of Nikken Sekkei Ltd.'s designers who helped create the world's tallest freestanding tower.