San Luis Obispo (/sæn ˌluːɪs əˈbɪspoʊ/; Spanish for "St. Louis, Bishop [of Toulouse]", pronounced [san ˈlwis oˈβispo]), or SLO (/sloʊ/) for short, is a city in the U.S. state of California, located 190 miles (310 km) north of Los Angeles in Southern California's Central Coast region. The population was 45,119 at the 2010 census. The population of San Luis Obispo County was 269,637 in 2010.

Founded in 1772 by Spanish Franciscan Junípero Serra, San Luis Obispo is one of California's oldest European-founded communities. Serra's original mission was named after the 13th-century saint and bishop Louis of Toulouse. The city, locally referred to as San Luis, SLO, or SLO Town (as its county is also referred to as SLO) is the county seat of San Luis Obispo County and is adjacent to California Polytechnic State University.

About SLO

The Madonna Inn is an eccentric landmark established by Alex Madonna in 1958. The Fremont Theater, an historic Art Deco theater from the 1940s, plays first-run movies on the huge screen. Murals adorn the walls of the main theater while neon swirls light the ceiling. The Palm Theatre boasts solar heating and is home to the San Luis Obispo International Film Festival. Since about 1960, people have been sticking chewed gum on the walls of Bubblegum Alley. The doctor's office on the corner of Santa Rosa and Pacific streets is one of very few commercial buildings designed by Frank Lloyd Wright. San Luis also has a Carnegie Library which is now home to the San Luis Obispo County Historical Museum.

The "underground city" is a series of tunnels beneath the city.

One of the largest Mardi Gras parades west of the Mississippi was held in San Luis Obispo, but canceled in 2005 because of difficulties related to crowd control and alcohol consumption.

A sculpture of a child and bear at the Mission in downtown San Luis Obispo. A fish was added after the photograph was taken.

Cal Poly's open house, Poly Royal, was held annually from 1933 to 1990. It was canceled in 1945 due to war rationing. It began as a show-and-tell for students to display their projects. It traces its origins to the 1904 Farmer's Institute and Picnic Basket. By the 1980s, as the college became "the most popular...university in the 19-campus CSU system", Poly Royal began drawing over 100,000 people from throughout the state, including 126,000 people in 1985. Concerts, parties, and other entertainment were added and it earned $3–4 million in revenue for the city every year.

Following a "mini-riot" in 1989 at an off-campus apartment during Poly Royal, the events in 1990 would cancel the event "indefinitely." Two nights of rioting on April 28–29 led to 127 arrests, over 100 injuries and 14 police injuries on top of "several hundred thousand dollars'" worth of damage. A liquor store near campus, Campus Bottle, was destroyed by revelers demanding alcohol. The second night was much larger than the first as people were leaving a concert on campus and parties off-campus were broken up and revelers flooded the streets. Mayor Dunin called the events "the worst experience in the history of San Luis Obispo." After a meeting between Mayor Dunin and University President Warren Baker the following Monday, Poly Royal was canceled from that point forward. The name Poly Royal returned in 2001 as "Open House Presents Poly Royal", a scaled-down version that was designed for students and parents. Another "mini riot" took place in the same neighborhood, across from Campus Bottle, in the early morning hours of March 7, 2015. Over 1,500 young adults converged on the area to celebrate "St. Fratty's Day." Several dozen students climbed onto the roof of a garage and the building collapsed.

San Luis Obispo has been home of several other events, including a stop on the way of the Olympic Flame Relay, the Tour of California bicycle race, Cinco de Mayo celebrations, and a long-standing Christmas Parade. In May, the Madonna Hotel hosts the annual California Festival of Beers, which includes beer tasting of over 200 craft beers. Another attraction is the development of Edna Valley into a well-known wine region. Just south of the city, people can spend an afternoon wine tasting several wineries in the area with a very short drive. The wine region extends north beyond Paso Robles (30 miles north) and south to Santa Ynez (70 miles south).

During summer months, a free outdoor concert Friday evening is called Concerts in the Plaza. Other noteworthy events include the San Luis Obispo International Film Festival, Festival Mozaic, a classical and crossover music festival, and the Plein Air Festival.

San Luis Obispo hosts a farmers' market where vendors sell food and goods and various visual and music artists perform.

Since June 2000, the first Thursday of every month is The Bike Happening (also known as Bike Nite) in San Luis Obispo. People gather at the Mission Plaza with their bikes. The bikers go around on multiple circuits on the main streets of downtown.

One of the cultural focal centers of San Luis Obispo is the Christopher Cohan Performing Arts Center built on the Cal Poly campus, which was constructed utilizing the donations of local businesses and individuals. The Performing Arts Center consists of multiple venues, including the original Spanos Theatre. The largest venue, Harmon Hall, seats 1,300. Many high school and college programs are scheduled. Local artists perform plays, music and dance. The addition of the Performing Arts Center attracts many touring performances which are usually not found in communities of comparable size to San Luis Obispo. The summer of 2007 was the opening concert of the Forbes Pipe Organ, which was built elevated into a side wall of Harmon Hall and required the donation of a further $3 million for purchase and installation.

The San Luis Obispo Museum of Art began in the 1950s when a small group of artists, educators and enthusiasts established the foundation. Over the years, the San Luis Obispo Art Association evolved into the San Luis Obispo Art Center, which evolved into the San Luis Obispo Museum of Art. The museum, with a focus on California Contemporary Art, shows 24 exhibitions per year, has both adult and children's art classes, and hosts art talks, films and other events. The museum launched a $15 million Capital Campaign for a new building in 2017.