Xiang Architects twists a double-helix observation tower above Chenhu Wetland

Xiang Architects has completed the Chenhu Migratory Bird Observation Tower on Xianglushan, a natural promontory within Wuhan’s Chenhu Wetland. Rising 19.8 metres, the structure overlooks Tonghu, the Tongshun River and a broad marshland that becomes a sanctuary for more than 100,000 migratory birds each winter.

Rather than treating the tower simply as a route to a viewpoint, the architects made the ascent itself the central landscape experience. The design slows movement through the structure, allowing changing heights, pauses and turns to gradually alter the visitor’s relationship with the wetland.

Two independent staircases coil in opposite directions to form a double helix, separating ascending and descending visitors. Along the routes, 24 staggered viewing platforms interrupt the climb. Close views of the surrounding tree canopy gradually give way to longer views across the marshland, breaking the 360-degree panorama into a sequence of framed perspectives.

Xiang Architects describes the experience through three perceptual stages: ascending, turning and overlooking. The staircases establish a continuous physical rhythm, while the platforms introduce moments to stop. The panoramic view at the summit consequently becomes the culmination of the journey rather than a detached destination.

The circulation system also determines the tower’s structural logic. Instead of a conventional central core, an interlocking stair-support system combines the stairs with counter-rotating steel braces. Opposing forces help resist torsion and leave a three-metre-wide void completely open through the centre of the tower.

Parametric modelling was used to rationalise the complex geometry into 24 standardised modules. The components were prefabricated off site and precisely assembled at Chenhu, a construction strategy intended to maintain geometric accuracy while limiting work within the sensitive wetland environment.

A matte silver metal skin wraps the structure. Its surface changes with the weather and time of day, appearing muted against wetland mist, reflecting blue skies in clear conditions and taking on warmer tones at sunset. The tower does not attempt to disappear into the landscape, but uses light and material to register its changing atmosphere.

By merging circulation, structure and observation into the same architectural system, the tower operates simultaneously as an object and a path. Each step becomes part of a controlled sequence between the visitor and the wetland, with the surrounding landscape continuously reconstructed through movement.

Project Credits

Project: Chenhu Migratory Bird Observation Tower
Location: Tonghu Town, Caidian District, Wuhan City, Hubei Province, China
Gross Floor Area: 303 m²
Architectural Design: Xiang Architects
Design & Completion Year: 2026
Photography: Chen Hao / @chenhao.etsam; mumu