The work has been carried out to clear trees and vegetation
The final stage of works on the A338 Bournemouth Spur Road has ended with traffic restrictions removed.
The verge clearance project started last month and is being carried out ahead of a £26m six-month refurbishment of the main route into the town.
A single-lane restriction at the Ashley Heath interchange, which caused major delays, has been lifted.
Some reptiles still need to be moved but this will not disrupt traffic, Dorset County Council said.
A spokesman added: "Once temperatures rise and the reptiles come out of hibernation, ecologists will begin rescuing those species that have not already been removed."
Ecologists carried out work to relocate a number of protected species of reptiles from the verges in November 2009.
The work has been carried out to clear trees and scrub vegetation and reclaim drainage ditches in the verges adjacent to the A338 to solve problems of carriageway flooding.
The lane restriction was initially put in place all day before it was moved to overnight in the final stages.
The reconstruction of 6.5 miles (10.5 km) of road and drainage systems is due to start in the autumn.