"You have to look for a rock lying on a rock," was the advice from our guide as we peered through our binoculars in search of a Saimaa ringed seal. Unfortunately, the best time to observe the seals was already over at the beginning of June. The best chances to see them are during the moult in May. "They don't like rain and they don't like wind", was another piece of information that our guide shared with us. Well, it was warm and dry and almost windless on our three-hour sunset tour. But only at the end, when I had almost given up on it, did we get to see two of these cute animals.

For my visit, I focused on the two national parks that are mentioned in the description on the Unesco website. I largely followed Juha's recommendations, his review was really helpful. I stayed for two days in Oravi village which is the logistical centre of the region. Here you can find tourist information, boat rental, supermarket, restaurant and reception all under one roof.
On the first day, I took a boat taxi to the island of Linnansaari. The one-way fare is 15 euros, but a minimum of 50 euros per boat. The regular service didn't start until mid-June, but luckily a family of four also wanted to go to the island, so I only had to pay the regular price. Five hours was more than enough for the hike to the Linnavuori viewpoint, and there was still time for a bit of sunbathing while waiting for the taxi back to Ovari. There is also accommodation on the island, right by the jetty is a campsite and some small cabins to rent. You need to bring water and food, the café at the campsite is only open in July and August.
The next day I visited Kolovesi National Park, hiking the Nahkiaissalo nature trail. From Oravi it is a one-hour drive (about 40 km) to the starting point of the trail. As mentioned by Juha, it is the only trail accessible by car. Kolovesi National Park consists mainly of islands, only narrow coastal strips on the mainland are included. 
I enjoyed these hikes in the forest, along the lakeshores with beautiful viewpoints and also unexpectedly steep cliffs. I only met a few other hikers, but was accompanied by annoying mosquitoes most of the time. And there are probably even more of them in high summer.

And now to the main thing: the "Sunset Seal Safari". Morning tours are only available in May during the moulting season, sunset tours are offered from June to September. Our tour started at 8 pm at the pier in Oravi. There were only five of us on the tour, so a small boat was sufficient. The tour goes far into the national park northwest of Linnansaari Island, an area with many small islands. And with many small rocks, the seals' favourite spots when they come out of the water. During the three hours on the lake we did not meet any other boat or canoes, it was almost completely silent, only our own noises and those of the boat, and now and then the cry of a bird. We saw ospreys, in flight and in their nest, and some other birds whose names I don't remember (I'm not so much into birdwatching). But no Saimaa seal, at first. But later, as twilight set in and the tour was already starting to get a little boring, we saw our first seal lying motionless on a rock (photo left). I would have needed better equipment than my standard camera and a higher zoom to take good and sharp photos in these light conditions. Especially as the boat keeps at least one hundred metres away to not disturb the animals. But with the binoculars (provided by the tour guide) you can observe these cute animals very well. And a few minutes later we saw a second seal. Just as I was wondering if it was really a seal or simply a stone or a sculpture of a seal (to fool the tourists), the "stone" slid elegantly into the water and swam past our boat at a safe distance. And the cherry on the cake was one of the most atmospheric sunsets I have experienced so far (photo right), although the sun has not really disappeared two weeks before the midsummer day.

The area around and between the two national parks is quite remote. I enjoyed hiking and driving there. There is almost no traffic, sometimes you see an elk running along the road. And sometimes you have to use ferries to cross the water. These ferries are free and run on demand, which means they come when a car arrives on the other side. However, you can only get a real impression of this lake landscape from the water, either with a boat tour or probably even better by canoe or kayak.
The Saimaa ringed seal is the focus of this nomination and probably the key element for inscription. But beyond that, I think this whole lake landscape is unique and special, at least on a European level. Hence a clear thumbs up from me.