National gallery is in fact a national museum of Icelandic artwork. For actual info about temporary exhibition, go to the official website of the National gallery of Iceland.
How to Find National Gallery of Iceland:
Fríkirjiuvegur 7, 101 Reykjavík, downtown
GPS coordinates of National Gallery of Iceland: 64.144145, -21.938964 Take me there!
Photos of the National Gallery of Iceland: