Free Solo,” the herculean tale of one man’s quest to climb Yosemite’s El Capitan mountain without a rope, has just cleared another massive feat.

National Geographic’s palm-sweat inducing film has now surpassed “RBG,” Magnolia Pictures and Participant Media’s feature of esteemed Supreme Court Justice Ruth Bader Ginsburg, as the second-highest grossing documentary of 2018.

“Free Solo” added another $1.38 million in its 19th weekend of release, bringing its total bounty to $14.98 million. It played at 483 venues this weekend, including over 350 Imax screens, marking its widest point of release to date. “Free Solo” has also generated an impressive $1.6 million in the United Kingdom, where it is now the biggest doc of last year.

“I love that the golden age of documentaries is not just relegated to the small screen. If there were ever a film to be seen on the big screen, it’s ‘Free Solo,'” said Courteney Monroe, president of National Geographic Global Networks. “It’s such an immersive and visceral experience that it almost gives you vertigo. You feel like you’re right there with Alex.”

The acclaimed non-fiction film, directed by filmmaker Elizabeth Chai Vasarhelyi and photographer Jimmy Chin, is now also an Oscar frontrunner after nabbing a nomination for best documentary feature. The exhilarating doc follows free soloist climber Alex Honnold as he prepares to scale the 3,000 foot El Capitan in Yosemite National Park without using harnesses or other gear.

It’s been a good year at the box office for features in the non-fiction space. Four documentaries surpassed $10 million in ticket sales in 2018, including “Won’t You Be My Neighbor” ($22.8 million), “RBG” ($14 million), and “Three Identical Strangers” ($12.3 million). Last year was, for good reason, dubbed the golden age of documentaries, though not all attempts resonated with audiences. Given the messy state of politics in D.C., it’s probably no coincidence that movies centering on uplifting protagonists like Honnold, Ginsburg, and Fred Rogers were able to strike a cord with moviegoers. Meanwhile, political docs like controversial pundit Dinesh D’Souza’s “Death of a Nation” ($5.8 million) and “Michael Moore’s “Fahrenheit 11/9” ($6.3 million) weren’t as fortunate.

The era of hot docs could continue after a slew of compelling titles debuted at Sundance Film Festival last weekend. Among the popular titles were “Ask Dr. Ruth,” featuring the famed sex therapist who survived the Holocaust; “Leaving Neverland,” an expose of sexual assault allegations against Michael Jackson; and “Knock Down the House,” a look at up-and-comers in politics such as congresswoman Alexandria Ocasio-Cortez.

“There’s probably never a bad time for a hopeful aspirational story,” Monroe said. “In Alex’s case, he is the embodiment of demonstrating that the impossible is possible. What a great inspirational message.”