The trail used by sightseers to reach the summit of Diamond Head for a panoramic view of Waikiki will be closed for a month for maintenance.

The Department of Land and Natural Resources says the work will include scaling of potential rockfall hazards along the trail trod by more than 600,000 residents and visitors a year.

The park area on the floor of Diamond Head Crater will remain open to the public during most of the work that's scheduled to begin Oct. 20.

However, the park will be closed Nov. 13-20 when rock scaling work is done above the tunnel that serves as the entrance to the crater.

The department says the maintenance is the first phase of the state's planned upgrades to the summit trail, including expansion of the trail to make it safer.