While the museum administration declined to say how many tickets were offered for the night visits, some netizens who were able to make reservations said nearly 3,000 tickets were left at the time the system resumed taking reservations for Wednesday after it crashed.

Aside from those who booked through the system, representatives also were invited from sanitation workers, express couriers, soldiers, police officers, firefighters and other groups of workers in appreciation for their year-round service to the public.

The enthusiasm for the special visits was clear: On a secondhand goods trading website run by taobao.com, a "free" entry ticket was being resold for about 1,000 yuan ($148).

Despite the exception, the curfew remains at the Forbidden City. No one except necessary staff, including a night patrol and a fire squadron, is allowed inside after sunset.