Observatory - the island
This island is really a jetty - and a sculpture, by the artist Gunilla Bandolin. She has this to say about the Observatory:
"The sculpture is a place and doesn't represent anything but itself. It lays, thread like a pearl, on the sight line that goes through Sickla Udde and points inwards to the city. Much like a house, it has both an inside and an outside. The roof is the sky."
(more about the Observatory, in Swedish, here )