Doc box office: 'Free Solo' becomes second biggest film released in 2018

But Peter Jackson's They Shall Not Grow Old ends up No. 1 over weekend

Alex Honnold climbs Yosemite's El Capitan without ropes in the documentary "Free Solo." Photo courtesy National Geographic

Free Solo still hasn't reached the summit of its box office potential after a remarkable 19 weeks in theaters.

The documentary about Alex Honnold's perilous ascent of Yosemite's El Capitan rock face -- without ropes -- made a stunning $1.25 million at the box office over the weekend, thanks to the addition of hundreds of IMAX screens. According to audience measurement firm comScore, the film by E. Chai Vasarhelyi and Jimmy Chin has now made a total of $14,851,341, pushing it past RBG, which finished its run with just over $14 million.

Only Won't You Be My Neighbor? made more money at the box office among nonfiction films in the past year, collecting $22.8 million.

Now's your chance to see the Academy Award-nominated Best Documentary Feature on the big screen! #FREESOLO is coming back to IMAX for one week only, starting Friday 2/1! pic.twitter.com/5lUgH9U1lz

— Nat Geo Channel (@NatGeoChannel) January 29, 2019

Free Solo and RBG are among the five feature documentaries that will compete for an Academy Award at the end of the month.

Free Solo's mega-weekend was not enough to make it number one at the doc box office, however. That honor went to Peter Jackson's World War I film They Shall Not Grow Old, which made $2.4 million. The 3D documentary, which features colorized war footage, has made a total of $10,778,647, comScore reported.

They Shall Not Grow Old played at 735 locations, versus 483 for Free Solo. Its per-screen average came in at $3,318, ahead of $2,589 for Free Solo.