Getting up before daybreak, tramping through parks and along the waterfront with your binoculars and fellow birders all day.
That Eureka moment when you spot a rare species, or a bird that hasn't been seen in the area in a very long time, capped off with a festive dinner to celebrate the day's discoveries.
What's not to like?
Sunday in Oakland, and Dec. 27 in San Francisco, some 400 Bay Area birders with the Golden Gate Audubon Society will take part in what's considered the largest and oldest citizen science project in the world.
The annual event draws more than 70,000 volunteer bird counters across the Western hemisphere in 2,300 locations, to track the health of bird populations.
Both beginning and experienced birders take part in the count.
Some navigate the bay in boats, while others trek through city streets, parks, creeks and mudflats to document bird sightings.
"For Bay Area birders, these two Christmas counts are an integral part of the holiday season," said past San Francisco co-organizer Dan Murphy.
The Oakland and San Francisco counts have ranked among the top 25 nationwide in terms of numbers of species found. And in recent years, the Oakland count has had more participants than any other effort in the world.
Last year there were 284 participants throughout the day, starting with "owlers," who get up before dawn to observe owls, said Dave Quady, a coordinator who has participated in the count for decades.
"We're very pleased with the numbers we get," Quady said. "For three recent years we had more field observers than any other Christmas count in the world."
The Oakland count typically records more than 170 species, and the San Francisco count tallies more than 160, Audubon officials said.
Oakland's count extends from Treasure Island northeast to the San Pablo Reservoir in Contra Costa County, and south to Saint Mary's College in Moraga and the Oakland International Airport.
The San Francisco count includes the north tower of the Golden Gate Bridge and all of San Francisco, and reaches down the peninsula to San Bruno Mountain and the wetlands north of the San Francisco International Airport.
Count participants gather at the end of the day for a dinner, to tally results and share stories of the day.
The count was started in 1900 by ornithologist Frank Chapman of the American Museum of Natural History in New York City wanted alternative to annual Christmas hunting contests. Instead of getting shot, birds would be counted.
Registration is closed for the Oakland bird count, and registration for the San Francisco count will close on Tuesday.