The frenemies shared a laugh and caught up at Givenchy designer Riccardo Tisci's birthday party Friday in Ibiza.
Kardashian and Hilton have known each other since childhood, and were best friends for many years.
The relationship crumbled as Kardashian's star rose, and Hilton once compared her former friend's rear end to "cottage cheese in a trash bag."
Kardashian posted a picture of herself with Hilton at the party Sunday on Instagram. She captioned the photo, "Reminiscing about the 1st time we went to Ibiza in 2006! @parishilton it was so good to see you & catch up!! Loves it lol."
Hilton reposted the shot with the caption, "So much fun with @KimKardashian this weekend at @AmnesiaIbiza. The first time we ever came to this magical island was together. Such an amazing trip! Great catching up with you too beautiful!"
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