The Red Thread: A Zig-Zag Bridge That Turns a Canal Crossing into a Linear Civic Plaza

Q: Who wrote "The Red Thread: A Zig-Zag Bridge That Turns a Canal Crossing into a Linear Civic Plaza"?

This article was written by UNI Editorial and published on uni.xyz, a platform for design professionals and creative thinkers.

Q: What is "The Red Thread: A Zig-Zag Bridge That Turns a Canal Crossing into a Linear Civic Plaza" about?

This article covers topics related to Infrastructure Design, Sustainable Design. A red upper cycle lane and a lower pedestrian plaza fold across the canal, trapping civic rooms between them and leaving a 25-metre gap for boats.

A red upper cycle lane and a lower pedestrian plaza fold across the canal, trapping civic rooms between them and leaving a 25-metre gap for boats.

5 min read·47 reads

Most bridges are judged by how quickly they get you off them. The Red Thread sets a different measure: how long it can make you stay. The project bends a canal crossing into a zig-zag, splits it into two separate streams of movement, and lets the overlaps between those streams become rooms. The result reads less like a span than a public square stretched over water, with a vivid red cycle lane drawn through it like a stitch.

Designed by Letizia Garbolino and Benedetta Leway, the proposal starts from a reading of the bicycle as one of the most resilient tools of urban transport, more than a century after its invention. Rising fuel costs, congestion, air pollution and the health case for active mobility frame the brief. The designers answer this context with infrastructure that serves cyclists and pedestrians differently, then argues that the space between those two groups is where the city actually happens.

Two Speeds, One Structure: Separating Cyclists from Strollers

The bridge carries two distinct circulation systems. The red cycling path runs on the upper level and gives the project its name and its colour. The pedestrian route sits lower and widens into a plaza over the canal. Pulling these flows apart is a practical move: commuters on bikes keep their momentum, and people on foot are free to wander, stop and gather without dodging traffic. The designers keep the two levels visually connected, so the separation never turns into isolation. Cyclists look down onto a lively deck, and pedestrians look up at the red line passing overhead.

The zig-zag is what makes this layering productive. A straight deck would simply stack two corridors. The broken polyline instead creates a sequence of angles where the upper and lower routes cross. At those crossings, enclosed volumes appear, housing programmes that would normally sit on the city's edge. The canal, in effect, lends space to the land. It is a sharp reversal of the usual logic, where water is the obstacle and the bridge is the shortest possible apology for it.

From Shoulder to Dock: Pulling the City Down to the Water

The intervention does not stop at the abutments. It continues from the shoulders of the bridge down to the docks, inviting people toward the canal instead of carrying them over it. Each edge has its own character. Along the cycle path, urban gardens soften the infrastructure and offer places to rest. On the opposite side, open seating and performance spaces leave room for unplanned public use. The lower pedestrian level works as a flexible civic platform where children can play, neighbours can meet and visitors can pause to take in the cityscape. Here the bridge stops being a corridor and becomes a destination, which is exactly the shift the designers are after.

Three Supports, a 25-Metre Gap and Two Reaching Hands

For all its civic ambition, The Red Thread remains working infrastructure. It rests on three structural supports on each bank and leaves a 25-metre navigational opening in the centre for maritime traffic. The movable parts are designed to blend with the fixed structure, so the bridge keeps its visual continuity even when open. That matters: a lifting bridge often looks broken mid-operation, while this one is meant to read as a complete object in both states.

The designers describe the form as two hands reaching toward each other from opposite sides of the city, interlocking to connect and pulling back to let boats through. The metaphor is useful because it explains the zig-zag as more than styling. The fingers of each hand are the folded segments, and the gaps between them are the public rooms. Layered and permeable, the structure offers shifting views across the canal, through the enclosed volumes and along the red lane, which gives the city a landmark that is easy to remember and tied to movement rather than spectacle.

Why This Project Matters

The Red Thread treats a bridge as a piece of city rather than a link between two pieces of city. That is a meaningful position at a moment when urban infrastructure is being rethought around low-carbon mobility. Instead of adding a bike lane to a conventional crossing, the designers build the whole structure around the idea that cycling and walking deserve different conditions, and that the interface between them can hold public life.

The project's strongest lesson is geometric. A single decision, bending the deck into a zig-zag, produces circulation, programme, shade, views and identity all at once, while the engineering of the 25-metre opening is folded into the same language. Whether or not every detail would survive construction, the proposal makes a convincing case that a canal crossing can be a plaza, a garden and a stage, and still let the boats go by.