Here is the basic information
Camp David is the country retreat of the President of the United States. It is located in wooded hills about 62 miles (100 km) north-northwest of Washington, D.C., in Catoctin Mountain Park near Thurmont, Maryland.[1][2][3] It is officially known as Naval Support Facility Thurmont and is technically a military installation; staffing is primarily provided by the U.S. Navy and the U.S. Marine Corps.
First known as Hi-Catoctin, Camp David was originally built as a camp for federal government agents and their families by the WPA. Construction started in 1935, and was completed in 1938.[4] In 1942, it was converted to a presidential retreat by Franklin D. Roosevelt and renamed "Shangri-La" (for the fictional Himalayan paradise). Camp David received its present name from Dwight D. Eisenhower, in honor of his father and grandson, both named David.[5] Camp David is not open to the general public. Catoctin Mountain Park does not indicate the location of Camp David on its official park maps due to privacy and security concerns
It has been used by every president. It has been used to meet with foreign officials and high level diplomatic meetings.
here is the link
http://en.wikipedia.org/wiki/Camp_David
on a personal note - way back when I was a student and security wasn't so high a level we used ro go picnicking in the Catoctin park