More than a million hours of labour have gone into a major road-widening scheme without a single accident.
A 170-strong team has been working on the 2.5 mile section of the A23 between Handcross to Warninglid since June 2012.
The road is being widened to create extra capacity on the busy commuter route.
Contractor Carillion has introduced health and safety measures, including a device attached to a hard hat, which vibrates when near operational machinery and equipment to alert workers to the danger.
The cost of the scheme is estimated at £76.9 million – a 23% saving on the previous estimate of almost £95 million.
Highways Agency project manager Chris Bacon said: “This is a big milestone and shows the dedication the team have to health and safety as they work around the clock, often just feet from live traffic.
"Road users also have their part to play and I would like to thank drivers for their continued patience while we improve the A23.
"I would also like to remind drivers that they have a part to play in keeping the workforce safe by driving safely.”