Temporary Closure of Waters Around Alcatraz Island
From 7/3 to 9/22 a 500’ marine buffer zone is in effect, closing the perimeter of Alcatraz Island to all private vessels to protect nesting seabirds during America's Cup racing. Tours to Alcatraz continue as usual during the races. More »
Muir Beach (but not nearby Muir Woods) closed July 8-November 2013, but local businesses are open
Though Muir Beach is closed from July 8-November 2013 due to construction, the PELICAN INN IS OPEN. Restrooms and parking are not available at Muir Beach. Pacific Way is closed except to residents. Check back for updates or call (415)561-3054. More »
CAUTION: Post Storm Damage to Coastal Trail
The Presidio Coastal Trail segment just north of the Pacific Overlook and adjacent to Lincoln Blvd remains CLOSED indefinitely. We have posted signage to alert bicyclists and hikers and with information for safe trail alternatives. More »
Marin Headlands Rotation Animation
Do large blocks of rock rotate? Geologic evidence says they can, and do. Based on fault patterns and rock paleomagnetics, there is strong evidence that the Marin Headlands block has rotated clockwise about 130 degrees since these rocks were added to the edge of North America about 95 million years ago. No one knows when this rotation occurred, but it is likely to be related to movement along the nearby San Andreas fault in the last 10 million years. Right lateral movement along that fault is thought to have caused the clockwise rotation of other large blocks of rock, particularly in southern California.
Can rotation of this block be responsible for the modern geography of the Golden Gate Straits?
The animation requires your monitor to be set to at least 800x600 resolution and you must have Flash version 8 or greater installed to play. You can get the latest version of Flash here for free.
Did You Know?
Alcatraz Island is one of the designated National Historic Landmark Districts and has over 1.4 million visitors, each year, from all over the world.