When viewed from the earth, the sun appears to not only move from east to west each day (due to the earth's rotation about its axis), but it also appears to move against the background stars (due to the earth's motion about the sun). The times when the sun reaches its highest and lowest point with respect to the stars (specifically the maximum and minimum points of declination) are the solstices. At the moment of solstice, the sun stops moving north (or south) and starts heading back the other way.
This year, the summer solstice occurred at 17:16 UTC on the 21-June-2011. This post has been made at the exact moment.
The weekend following the solstice is the mid-summer break, which is widely celebrated throughout Fenno-Scandinavia. The KAIRA construction project will take a few day's break during this time (although we'll continue to post web log articles... if nothing but to try to catch up on the back log!).
PS: The photograph is genuinely the view across Siilasjärvi at midnight on 18th/19th June 2011. For the solstice itself (well, with 5 minutes to go as I type this), it was 5 degrees celsius... and raining hard.