Sara Nordström, who is from Örebro in central Sweden and is still at high school, signed up to an online project called TwinStrangers.com, which links people with similar facial features.
She spotted a photo of Shannon Lonergan, 21, a business student from County Kerry in Ireland, and used the site to send her a 'star' alerting her of their likeness.
Lonergan didn't reply, but the website's team connected the two young women after being astonished by how similar they were, and arranged for them to meet up in Ireland.
“It felt a bit surreal (…) a bit like looking at yourself,” said Nordström.
Lonergan added: “The scariest thing was how our noses, mouths, lips and eyes were so incredibly alike. It frightened me a little bit (but in a good way!) As I spent more time with her I noticed how our expressions and ways of moving were exactly alike.”
She said that the girls shared a passion for sports and that, bizarrely, both of their parents owned furniture shops.
“Sara was a little more shy, but before too long we talked and acted like we had known each other for years (…) You bond very quickly with someone who has your face!”
Both 'twins' said that their families had been a little unnerved by the pair's likeness.
“Shannon's Dad thought we could both be his daughters which was kind of crazy. He was definitely a little freaked out!” said Nordström.
The girls are hoping to remain friends, despite living more than 2500km apart.
“We added each other on every existing social networking site so I know we'll stay in touch! (…) The experience was one in a milion!” said Lonergan.