The Chinese authorities restrict visitors to Tibet, so the bicycle rally is an unusual and relatively inexpensive way to see areas of the Tibetan countryside that tourists rarely visit.

"But just because we live here, there shouldn't be a sign restricting visitors," Mr. Hildreth said.

Other areas such as the Palace of Quetzalcoatl, the Site Museum, the Citadel and others are all closed off, restricting visitors to the open areas of the Avenue of the Dead and the plazas around the two pyramids.

Park rules restrict visitors to the trail and visitors are also requested to respect this historical site by leaving any artifacts where they find them.

Ontario health officials ordered Toronto area hospitals this week to restrict visitors and require all hospital staff to wear masks and other protective clothing.

There were signs on the walls reminding nursing staff to follow sterile procedure and restricting visitors, and several of the doors had signs on them prohibiting entry without Clean Room protocols.

Because Wadi El-Hitan is within the Wadi El-Rayan Protected Area, the same protection management plan restricts visitors to prearranged guided tours along a prescribed trail.

Most are resisting transitional housing regulations, Mr. Levy said, because they restrict visitors and punish welfare recipients for missed appointments.

"We have guaranteed the Tlulaxa their privacy, and we respect their wishes to restrict outside visitors," the Grand Patriarch continued.

Vicki Ciampi, the hospital's public affairs director, said Bellevue's policy permits a wife to restrict visitors to her husband and that the hospital had complied with Mrs. Vlasto's request.