Tunneling is officially underway on Metro’s Purple Line subway extension to the Westside of Los Angeles.

The first round of tunneling started Tuesday beneath the intersection of Wilshire Boulevard and La Brea Avenue.

Twin 450-foot-long tunnel boring machines (dubbed Elsie and Soyeon) will carve out about 60 feet of tunnel daily for the next two years, en route to the Wilshire/Western station, where Purple Line trains now turn back for Downtown Los Angeles.

The first phase of the Purple Line extension broke ground in 2014 and is expected to open in 2023. The $2.82 billion project will add a little under 4 miles of track to the subway route, bringing it to the intersection of Wilshire and La Cienega boulevards.

Eventually, the extension will bring the train all the way to the VA hospital, just west of the 405 on the border of Westwood and Brentwood. The project is being constructed in three segments.

Phase two will run between La Cienega and Constellation Boulevard in Century City. The third phase will add a stop near UCLA en route to the VA.

Altogether, the extension will add roughly 9 miles to the Purple Line and is expected to carry nearly 60,000 riders daily.

But the project isn’t popular with Beverly Hills residents and school officials who have sued repeatedly to block the second leg of the project, arguing that tunneling work beneath the Beverly Hills High School campus could pose a threat to the safety of students. Metro officials have steadfastly denied these claims.

Last week, students, teachers, and school administrators in the city gathered at Will Rogers Memorial Park to protest the subway project.

Tunneling work hasn’t started yet on the second phase of the project, and Metro spokesperson Dave Sotero told Curbed last week that the agency selected a route that travels beneath the high school because that route “provides the greatest benefits with fewest impacts.” Another proposed route along Santa Monica Boulevard would have intersected with an earthquake fault.

Sotero says Metro will continue to look for unmapped oil wells beneath Beverly Hills out of “an abundance of caution.”

Protests and legal challenges notwithstanding, Metro expects all three phases of the project to be complete by 2026.