The Canterbury Earthquake Recovery Authority has reduced the cordon around the Christchurch CBD from 11am today.
A temporary pedestrian corridor through Cathedral Square from the Worcester Street Bridge to the intersection of Gloucester and Colombo Streets will remain in place until demolition in the square begins.
Parts of High Street, between Cashel and Lichfield Streets, and between Lichfield and Tuam Streets, will be reopened to pedestrians.
"Immediately after the February 2011 earthquake the central city cordon covered 387 hectares. By April this year it had reduced to 38 hectares, and today's reductions reduce it further still," Canterbury Earthquake Recovery Minister Gerry Brownlee said.
"The cordon reductions will continue until the rebuild zone cordon is removed completely, most probably in June."
See a map of the cordon here.