For many first-time drivers in the UK, one perplexing feature is the presence of traffic lights at roundabouts. For drivers from Hong Kong, the confusion is often compounded by the dense and overlapping lines on the road, which can appear chaotic and leave them uncertain about which lane to take.
This unease is understandable. Hong Kong drivers are accustomed to simple, single-flow intersections; when faced with the multi-lane, spiral, and segmented traffic light-controlled roundabouts of the UK, they may instinctively react to the complexity with a sense of disorder. However, the issue lies not in the number of lines but in a lack of education on how to interpret them. The overlapping dashed lines are not mere decoration; they clearly indicate which lane you are in and where you will be naturally guided to exit, eliminating the need for abrupt lane changes mid-way.
Another key reason for the existence of traffic lights is often overlooked: they are not intended to ‘stop traffic’ but rather to allocate it. Roundabouts without traffic lights may seem to allow free passage, but they can easily lead to structural imbalances. If one direction experiences a continuous flow of traffic, downstream entrances may have no gaps to merge into, causing traffic jams that can spill over and paralyze surrounding roads. By introducing traffic lights, engineers can enforce time-based traffic flow, ensuring that each direction receives a basic and predictable release period, thus distributing traffic more evenly across the junction.
Consequently, at roundabouts with highly asymmetrical traffic flows or those directly connecting to major roads, traffic lights serve as a tool to maintain overall throughput rather than being an obstacle. They sacrifice local, momentary free flow in exchange for the stability of the entire road network. For drivers, red lights may seem superfluous; for the system, however, they act as a safety valve to prevent queue chaos.
In fact, this encapsulates the logic of British road engineering: traffic lights govern temporal order while road markings manage spatial order. Together, they deconstruct potential conflicts that would otherwise occur simultaneously into sequential driving paths. While this may initially appear complex, it effectively offloads the most challenging judgments to design, rather than leaving drivers to navigate uncertainties at the junction. Once drivers understand the meaning of each set of dashed lines and select the correct lane before entering, the entire roundabout can operate surprisingly smoothly.
Looking back at Hong Kong, it is not entirely stagnant. In recent years, several roundabouts have gradually transformed into ‘spiral junctions’, attempting to guide vehicles to naturally shift outward along the lanes, thereby reducing lane cutting and abrupt lane changes. However, the problem lies in the fact that this transformation is often only partially completed: the old driving intuition of ‘fast inside, slow outside’ still persists, while the new markings suggest a different driving logic. As a result, some drivers insist on staying in the inner lane while others follow the new markings to the outer lane, leading to collisions between two conflicting understandings at the same junction, making accidents and friction inevitable.
The experience of the UK clearly illustrates that for spiral junctions to function effectively, traffic lights are often an indispensable element to balance the flow of traffic between different directions. An incomplete system will only create more grey areas. The problem has never been about whether the design is too complex, but whether the city has the resolve to complete that complexity in one go, rather than leaving drivers to guess under half-new, half-old rules.
