4. Henderson Waves Bridge
This nearly 900-foot pedestrian bridge is the highest of its kind in Singapore, connecting two parks. The bridge has a wave-form made up of seven undulating curved steel ribs that alternately rise over and under its deck. The curved ribs form alcoves that function as shelters with seats within.
The sinuous Pythonbrug is one of the most modern bridges in Amsterdam, a city famous for its traditional canal bridges.Â Unlike Singapore's Henderson Waves, which relies on an outer shell to create the wave illusion, the Pythonbrug walkway actually dips and rises. While the bridge is certainly an eye-catcher, MacDonald points out that its steep incline wouldn't pass muster under the Americans With Disabilities Act, which sets a 5 percent limit on the grade of such structures.
8. Oresund Bridge
The Oresund Bridge is an incredibly complex structure that begins as a cable-stayed bridge in Sweden and ends as a tunnel in Denmark. A small artificial island was built around the tunnel's entrance to keep water from creeping in. Not only is the bridge equipped to handle four lanes of traffic.
The Slauerhoffbrug is a tail bridge that can quickly be raised to allow ships to pass. It was completed in 2000 and spans a small section of the Harlinger Vaart River. Instead of rotating open, the Slauerhoffbrug is lifted up by a dual hydraulic systems that is built into its pylon. The Slauerhoffbrug is L-shaped, with its foundation sitting adjacent to the road.