The Swedish capital’s metro, or tunnelbana, has been described as the world’s longest gallery, with art permanently on display at 90 of the 100 stations along the 68-mile tunnel system. The decades-old permanent works grapple with issues from women’s rights to inclusivity and deforestation.

But a provocative new exhibit has proved particularly controversial among commuters, sparking debate about the role of public art – and whether the wait for the train is the right time for breaking taboos.

Graphic artist Liv Strömquist’s series of enlarged felt-pen sketches have been on display at Slussen station for the past five weeks. The Night Garden shows cartoon birds, cats, trees, naked men – and women with unshaven legs and visible menstrual blood.

One image, of an ice skater in repose with a red stain on her leotard, is captioned: “It’s Alright (I’m Only Bleeding)”.

Strömquist, the author of six books, is known for her satirical and feminist perspective. She has said the series was inspired by the “pastoral idyll” genre, and sought to convey a sense of tranquility to stressed-out commuters. Read more