While there are up to 300 hikers allowed on the Half Dome cables per day, there are far MORE people who want to hike the route. The permit lottery is now open. If you want to hike Half Dome, sign up at www.recreation.gov or call 1-877-444-6777.
You can also sign up for the two-day-in-advance permits through www.recreation.gov.
From the press release:
Hiking to the top of Half Dome is one of the most popular hikes in Yosemite National Park. The iconic granite monolith, at 8,842 feet above sea level, attracts people from all over the world who attempt to climb to the summit. Most visitors ascend Half Dome via the cables, which are typically in place from mid-May through mid-October. Most visitors begin and end their hike at Happy Isles in Yosemite Valley. This is an approximately 17 mile round-trip journey.
Remember: Permits Required Seven Days Per Week to Hike Half Dome Cables.
The lottery is open through March 31, 2013.
You can read the original press release HERE.
You can find out more about the Half Dome hike HERE and HERE.
You can find out more about hiking safety in Yosemite National Park HERE.