Aka the Kotka Maritime Festival.
An annual 4-day festival held in Kotka, Finland around the end of July since 1966.

Events and activities include concerts, cruises, street theatre performances, competitions, a maritime fair and starting this year even a beauty pageant. The organizers say they're aiming for an image of a festival for the whole family, and have moved much of the events away from downtown Kotka to the harbor area.

Sources: www.kotka.fi, A program on Yle and personal experience.

And now for the obligatory GTKY part...

I visited the Meripäivät once a few years ago, in 1997 to be exact.
I had just turned 18, and was still operating under the illusion that boozing would be cool. A FOAF invited a few of us over to his summer cottage for the weekend, and as we know any excuse for drinking is good enough for Finnish teenagers. :)

After a small pre-party in my friend's mom's apartment the night before, five of us left Hämeenlinna towards the southern coast. After purchasing essential supplies (read: a little food and a lot of alcohol) we took a bus to the cottage which resided approximately 10 kilometers from the downtown area.
Being the patriotic Finns we are, we started on the liquor early on Friday afternoon. There were 10-12 people present, half of whom I had never met before. But we were taking care of the problem in the traditional Finnish way - filling our blood steam with ethanol.

Somehow, all of us managed to get into a bus headed for the city centre. Despite my intoxicated state, I immediately realized what the festival was all about:
50% of Finland's population gathering to a small town for drinking themselves unconscious.

The streets were packed. A person from Tokyo wouldn't have suffered from any symptoms of homesickness, that's for sure. Lots of drunken Finns, trash and noise. There didn't seem to be any events going on, and everybody seemed to be wandering around randomly getting more and more drunk.
After walking around the streets for a while, we realized there were no events for young people. A few concerts were going on nearby, but paying over 100FIM to see Finnish easy listening artists live didn't feel too appealing to me, as it wouldn't to anyone under 50.
So, we decided to visit a few bars. Good idea. Outside it was crowded, but inside in a pub things were just insane. A fire inspector would've had a field day closing down 100-person-capacity bars holding 250 people, but they were most likely getting wasted themselves. Not being able to supply any lemon for tequila didn't make me rate the joints high, but at this point I was numb enough to not really taste anything anyway.

And this kept up for several hours.. Walking around the town, cursing the lack of things to do and growing more and more bored as the blood alcohol level slowly began to drop. Our group had been dividing all through the evening. Around 1 there were only three of us: me, my best friend and his girlfriend. Starting to get a bit pissed off at the noisy masses, we decided it was time to head back for the summer cottage.
Unfortunately, we had overheard that there were no more buses going at this hour. In a genuine drunken Finnish pioneer spirit, we decided to walk. Only one of us had visited Kotka prior to this weekend, and even he couldn't tell where the hell we should be going. After climbing to a high hill we spotted a familiar looking bridge. It took us ages to actually get on it, but once we did the direction was clear.

And thus began our epic journey towards a place to sleep in. When you're tired, hungry and experiencing the first effects of hangover, hiking a 10km distance isn't the first thing you'd want to do. Still, all of this would've been Ok... if every single streetlight along the way wouldn't have been turned OFF.
Finland has its reputation as the land with the midnight sun. But during late July, it is already quite dark at night. Since there mostly only trees surrounding the road, and very few cars moving at that hour, we had to walk practically blinded. And none of us were 100% positive we were even walking on the right road.
We finally made it back to the cottage, only to have our host inform us that there would've been buses running too.

While this was certainly one of the suckiest experiences in my life so far, we weren't the most unlucky ones. The two other guys from Hämeenlinna had accidentally walked in the opposite direction for 4 kilometers, before noticing their error. They showed up in our tent in the morning along with a wide array of Finnish swearwords and curses. :)

What about Saturday night then? I stayed at the cottage getting drunk with a few others. At least it was less crowded and noisy.
A year later, the guy we had stayed at attempted to organize a rave so that there would be something to do for young people. The city of Kotka wasn't very interested in funding such an event, ergo, the plans were destroyed.

Any point in this long and boring story?
Although it may be just fine and dandy for the older folk, Kotkan Meripäivät is an another good example of nothing being arranged for the younger Finnish generations. I haven't visited the festival since 1997, but if a "disco" is the only even closely youth-related item on this year's timetable, things don't look good. There might be some unofficial events, but I am unaware of such. While I myself have grown past the compulsive drinking age, I'm sure many current teens feel the same I did 4 years ago.
At least time is on my side. In a few decades I might very well be the bitter old man interested in boats and Juha Vainio. :)