"Get in line !"

The rangers at California's Yosemite National Park, who last summer moved to reduce crowding and mishaps on the cables near the top of Half Dome by requiring hikers to reserve weekend permits, have decided to make those permits an everyday requirement.

The Half Dome cables are generally in place from mid-May through mid-October, depending on the weather. The first permits will be available at 7 a.m. March 1 for climbing the cables in May and June.

The permits – which are expected to sell out rapidly – limit foot traffic on the Half Dome Trail to 300 day hikers and 100 backpackers per day, with no same-day permits issued. The permits will be made available three months in advance, at the beginning of each month. So if you want to climb in July, it’s wise to try for a permit reservation on April 1.

Although the National Park Service likes to describe the permits as free, every permit requires a nonrefundable $1.50 “service charge” that goes to the concessionaire that handles the permit.

Park officials said the permit requirement was prompted by the growing popularity of the Half Dome route. Once the park started requiring permits on weekends, the number of weekday hikers increased dramatically, leading to the same safety worries the led to the permit program in the first place.

Before the permit system was put in place, a park service study found that as many as 1,200 hikers per day were hiking near the summit of Half Dome, steadying themselves on the granite rock face by gripping a pair of cables on stanchions for the final 400 feet of ascent. (The Sierra Club placed the cables in 1919.) From 2006 to 2009, four hikers died in falls on or near the cables.

Last summer, once permits were required for hikers on Friday, Saturday, Sundays and holidays, rangers say rescues and accidents on and near the cables dropped noticeably, and there were no deaths.

Moreover, park spokeswoman Kari Cobb said, "we noticed a major difference" in how prepared the permit-bearing weekend hikers were, versus the weekday, non-permit hikers. Many of the people without permits, she said, "were still showing up with Tevas on, without enough water, not enough food, or no lights."

Now the same restrictions will cover every day that the cables are up.

Permit reservations can be made at the Recreation.gov website or by calling (877) 444-6777. Each climber will be required to have his or her own permit, and up to four permits may be obtained under one reservation.

The Half Dome Trail, a 17-mile round trip, gains 4,400 feet in elevation from the valley floor. Hikers typically take 10 to 12 hours to complete it. Technical rock-climbers are still free to climb without permits, so long as they first summit Half Dome by other means and then descend using the cables.

Above, climbers, using cables, make their way up Half Dome at Yosemite National Park. (Photo by Scott Gediman)