NEW YORK - (AP) - Officials at the National Sept. 11 Memorial areinstituting a ticket reservation system to manage what they expectto be heavy demand.

Starting today, visitors can make reservations online. Thememorial opens to the public on Sept. 12, following events forvictims' families on the attack anniversary a day earlier.

Reservations will be required because the parts of the memorialplaza that will be open to visitors in September can onlycomfortably hold 1,500 people at a time.