SAN FRANCISCO (CBS SF) – As the Bay Area faces an unprecedented 12th consecutive Spare the Air Day due to poor air quality from wildfire smoke, several venues remain closed Monday.

At the Golden Gate National Recreation Area, operations remain suspended at Alcatraz, Muir Woods and Fort Point.

READ MORE: 1 Dead In Castro Valley House Fire

Other facilities in the GGNRA closed Monday include The Warming Hut at Crissy Field, Marin Headlands Visitor Center, Lands End Lookout, the Point Bonita Lighthouse and the Golden Gate Bridge Welcome Center.

Meanwhile the Presidio Visitor Center will remain open.

The Oakland Zoo, which has been closed since the 15th, has suspended operations again on Monday. Zoo officials said the animals are being monitored closely and have access to indoor facilities.

Numerous schools and colleges also remain closed Monday due to the smoke. A full list can be found here.

READ MORE: San Jose Police Struggle To Keep Up With Sideshow Enforcement Efforts

Smoke from the Camp Fire burning in Butte County has continued to pour into the Bay Area, which has led to unhealthy levels of particulate matter throughout the region for the past several days.

“It appears to be the worst air quality ever experienced in San Francisco,” Dan Jaffe, a professor of environmental chemistry at the University of Washington, told CNN last week.

The poor air quality has prompted the cancellation or postponement of countless events, including the Big Game between Cal and Stanford. Stores throughout the area have also reported a shortage of N95 masks, as people throughout the region look to protect themselves from the bad air.

Relief from the smoke is expected to finally arrive by midweek, as a storm is expected to bring much needed rain to the region.

The most destructive wildfire in California history and the deadliest U.S. wildfire in a century, the Camp Fire is 66 percent contained as of Monday morning.