 Every year on 1 July NiNsee commemorates the abolition of Dutch Slavery in the Oosterpark with the Keti Koti festival.The Oosterpark also contains a memorial to Theo van Gogh, a film maker and controversial columnist who in 2004 was murdered nearby by a Muslim extremist.Along the park towards Linnaeusstraat (close to the Royal Tropical Institute) there are a number of grey heron nests.