The sun set over Cambridge as thousands of spectators clustered on the Esplanade.

Families marked their territory with lawn chairs and blankets. College students sprawled on the grass and munched on nachos and fruit salads. One couple sipped wine: he with white, she with red.

This diverse crowd was brought together for the opening night of the Boston Landmarks Orchestra’s first summer concert series at the Hatch Shell last Wednesday.

The concert, which was sponsored by Classical 99.5 WCRB Boston and underwritten by the Boston Globe Foundation, was free to the public and featured works by Franz Joseph Haydn and Ludwig von Beethoven.

At about 7 p.m., Ray Brown, WCRB host took the stage to introduce the series.

“It’s going to be the best series in many, many, many summers,” he said to the crowd.

Brown then presented Charles Ansbacher, the Landmarks Orchestra’s conductor, who warmly greeted the audience.

Ansbacher founded the orchestra in 2001 as a way to allow freelance musicians in Boston to perform during the winter months, when the Boston Symphony Orchestra and other major groups are not playing.

Since then, the Landmarks Orchestra has consistently provided free outdoor performances for Boston residents.

“People love to go to concerts under the stars,” he said. “And I love to bring music to people in non-traditional settings.”

The orchestra began the evening with a powerful performance of Haydn’s “Symphony No. 104 in D major, ‘London.'” The half-hour piece began with a blast from string and horn sections, as the timpani rumbled underneath.

The unstable first part was followed by three diverse movements: one slow, one joyful and the last maintaining a long and triumphant theme.

Haydn’s piece was proceeded by a performance of one of Beethoven’s most well-know works, “Symphony No. 9, Opus 125 in D minor, ‘Choral.'” Enduring almost an hour, the four-movement piece climaxed with an orchestral and choral rendition of the monumental “Ode to Joy” theme.

Ansbacher said he chose these pieces to show that the orchestra performs “substantial” classical works.

“They’re monumental pieces and I thought that we wanted to make a statement that we’re about playing very good music and playing it well,” he said.

The concert was followed by a standing ovation, with screams and whistles piercing the crowd’s clapping. Many audience members said they were pleased with the song choices, the location and the evening in general.

Middler political science major Sarah LaMonaco heard about the performance through her sister, Kate, who works as Ansbacher’s assistant. She said she enjoyed the performance and it was important for the music to be accessible.

“I think they picked a great opening piece,” she said. “And the end of Beethoven’s [Symphony No. 9] was really powerful.”

Lucy Bullock, a middler political science major, attended the concert with Sarah and two other friends. The former clarinet player said it was important to take advantage of the city’s summer events.

“We’re trying to get out and experience cultural Boston,” she said. “Our first stop was the Landmarks.”

Ansbacher said he was pleased with Wednesday’s performance and the Hatch Shell was an ideal location for the evening.

“It’s a socially non-threatening environment where you can lie back and watch the sunset and hear music that is not usually very available,” he said.