His ballsy exhibition has 282 penises of different shapes and sizes, from 93 different species of animal across the globe.
Sizes vary from a huge sperm whale's 1.7-metre phallus - the largest exhibited - to the tiny penis bone of a hamster. Among the genitals on display are those of a polar bear, dolphins, a walrus, fish, an elephant and a man. Visitors can also look at a range of genital-themed artefacts. Hjartarson's bizarre fascination began as a child in 1974 when he was given a bull's penis to use as a whip on animals and he opened his museum in 1997 with 62 specimens.
He told AFP: "Some of my teachers used to work in summer in a nearby whaling station and after the first specimen they started bringing me whale penises, supposedly to tease me.
"Then the idea came up gradually that it might be interesting collecting specimens from more mammalian species."
The fascination for all things penis has even become a family business. Hjortur Sigurdsson, the founder’s son took over in 2011 and set about modernising the museum.
"It all started as a joke. My father had fun just collecting, doing something no one has done before. He always said 'somebody had to do it." He told AFPVisitors can pick up souvenirs like "Designer condoms" and woollen "willy warmers", knitted to resemble a snake and an elephant's trunk.
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