Thousands of exuberant music lovers of all ages converged on San Francisco’s Golden Gate Park last weekend for the annual Hardly Strictly Bluegrass Festival, a three day celebration of folk music and those who enjoy the blues.

The free concert featured an eclectic mix of singer-songwriter styles, including much more than just bluegrass, and instead exposing a variety of artists representing different forms of folk and rock and roll.

Attendees and event volunteers agreed that their favorite part of the event is the amount of spirit, energy and intoxicating love for music.

On Friday, festivalgoers enjoyed the Blue Angels flying overhead, as they were performing in San Francisco

Music fans were geared up for a day in the park: coolers, blankets, lawn chairs, sunglasses, and perhaps a partially hidden bottle or a four-legged friend on a leash.

Younger attendees were very excited on Friday to see a surprise reunion of Conor Oberst’s Mystic River Band, including Jenny Lewis and the Watson twins. Earlier in the day, Ben Kweller and Chris Carraba each took the same stage.

The highlight of the day for many older fans was the closing song of Elvis Costello’s solo performance, “Hide Your Love Away,” during which the crowd erupted in chorus all the way to the concession stands.

On Saturday and Sunday, over seventy other acts took the festival’s six stages.

Up and coming folk rock band, The Lumineers, played the festival for their first time. Their most popular songs include “Dead Sea” and “Ho Hey,” which peaked at number one on both the Billboard US Rock Songs and US Alternative Songs charts.

Others like Emmylou Harris, Nick Lowe, and Steve Earle & the Bluegrass Dukes have made many regular appearances over the years and were on stage Saturday at the delight of many Hardly Strictly fans.

This year was the first festival since the passing of founder and lone sponsor of the event, Warren Hellman.

Hellman, a San Francisco banker and venture capitalist, designed the concert with the help of booker Dawn Holliday and producer Sheri Sternberg in 2001 to be completely free and noncommercial, with nothing to detract from the music.

Back then, only Bluegrass acts were invited to play, and thus the show was called Strictly Bluegrass. In later years, the variety of styles expanded, so the word “hardly” was added to proclaim this change.

Hellman personally endowed the festival to continue for the next 15 years without any commercial sponsorship, and several attendees were holding back tears while remembering him and expressing their gratitude for his gift to the city.