The A45 Chowns Mill ‘throughabout, half-hamburger, walnut whip, moon and sun’ roundabout – Mark Roxburgh – National Highways

WINNER : Overall Best Paper 2023

In 2021 National Highways completed the improvements to the A45 Chowns Mill roundabout following nearly 20 months of work. The scheme has delivered improved capacity, safety and walking/cycling routes. This paper explores the origins of the scheme, what other options were considered, the design philosophy behind the final layout and how the signalisation was developed, tested and implemented.