For long it was thought that only modern human was capable of creating and/or using art. It turn's out that is not the case.
We are lucky enough that Slovene archaeologist have found what is considered to be the oldest musical instrument, flute to be exact, ever found in the World. Found in 1995 and for long under thorough examination until they've realized it has to be somewhere from 50.000 to 60.000 years old! At that time modern human, homo sapiens sapiens, haven't even existed.
You can and should see the flute on a display in a National Museum of Slovenia in Ljubljana, but there is something else I strongly recommend you to do. Visit it's archaeological park not far from Cerkno.
For visiting Divje Babe Archaeological Park check their web page. Keep in mind that the surrounding of the park is so beautiful you will not want to leave. Wear comfortable shoes as there is some walking to do and you do enter a cave. The entrance to the cave requires some physical strength as there is about 15 minute long hike on a steep slope. First down, than up.