A map

This butterfly is simply called map (Araschnia levana), landkaartje in Dutch. It gets it name from the pattern on the bottom side of its wings.

There are two versions of this butterfly: a summer version, which is black with white markings, and a spring version, like the one I saw the other day on one of my walks:

^{Olympus Stylus 1s, 300mm, ISO200, f5.6, 1/160s}

Here's a photo from the side, showing said markings:

^{Olympus XZ-1s, 112mm, ISO100, f5.6, 1/320s}

It lays its eggs on the bottom side of nettle leaves, so if you want to see this butterfly in your garden, you will have to leave the nettles alone!