
A team led by Xu Weiguo at Tsinghua University's School of Architecture completed the world's longest 3D-printed concrete bridge in Shanghai.

The bridge took 450 hours to produce and was unveiled in January 2019. Scroll through the gallery for some of the world's most spectacular bridges.

Lucky Knot Bridge by NEXT Architects, in progress (Changsha, China) —
The name and shape of NEXT Architects' Lucky Knot Bridge refers to the Chinese art of decorative knotting, which is associated with good luck.

Danjiang Bridge by Zaha Hadid Architects, in progress (Taipei, Taiwan) —
At just over 3,000 ft, the Danjiang Bridge -- one of the last commissions awarded to the late Zaha Hadid -- will be the world's longest single-tower, asymmetric cable-stayed bridge, according to the firm. The subtle design is meant to have visual impact without obscuring the Taipei sunset.

Sölvesborg Bridge by Ljusarkitektur, 2013 (Sölvesborg, Sweden) —
In a rare twist, the Sölvesborg Bridge -- Europe's longest pedestrian bridge at 2480 feet -- was specially enhanced by a lighting design firm rather than an architect. Ljusarkitektur mounted the structure with color-change LED lights.

Helix Bridge by Cox Architecture, 2010 (Marina Bay, Singapore) —
When it opened in 2010, Singapore's Helix Bridge was the first to incorporate the shape of a double-helix. The structure is meant to symbolize life, renewal and growth, and sits near Moshe Safdie's $5.7 billion Marina Bay Sands casino.

Køge North Station by COBE, in progress (Køge, Denmark) —
There's more than meets the eye with this structure. The bridge, designed collaboratively by COBE Architects Dissing + Weitling and COWI, includes passageways for both trains and cars, as well as a full station and park-and-ride facilities. It's set to open in 2018.

Puente Laguna Garzon by Rafael Viñoly Architects, 2015 (Garzón, Uruguay) —
Uruguayan architect Rafael Viñoly's circular bridge can only be truly appreciated from above. The circular bridge, which replaced a raft crossing, creates the effect of a lagoon within a lagoon.

Sarajevo Bridge by BCQ Arquitectura Barcelona, in progress (Barcelona, Spain) —
BCQ Arquitectura Barcelona's plant-covered bridge takes Heatherwick's green concept one step further. Their proposed upgrades to the existing Sarajevo Bridge include photoluminescent stones to light the pathway without electricity and concrete that converts pollution into harmless substances. As of now, there is no set completion date.

Cirkelbroen by Olafur Eliasson, 2015 (Copenhagen, Denmark) —
Artist Olafur Eliasson was inspired by the city's history as a port town when he designed Cirkelbroen. The five round platforms and wired masts give the illusion of boats floating on the harbor.

Zhangjiajie Canyon Bridge by Haim Dotan, in progress (Zhangjiajie City, China) —
Haim Dotan's Zhangjiajie Canyon Bridge is the largest glass-bottomed bridge in the world. Aside from supporting visitors, the bridge, which is 69 feet long and 718 feet high, will be also be used for bungee jumps and fashion shows.