Siiri offers all kinds of bouldering from delicate slab -climbing to hard roofs - but suites best for those who already feel comfortable climbing grades from 6A and above. Most of the climbing is on good holds (esp. on the Big block) with skin -friendly, smooth rock, which makes climbing as "indoorsy" as it can get on real rock.
Nowadays the area is pretty much fully developed, but some new routes pop up every now and then. On top of that, Siiri offers almost endless opportunities for making variations, links, and traverses of your own.
Having said that the rock is smooth and the holds are good, Siiri makes a great place for having a session on hot summer days as well. Being a bit shady and mossy it's not the first place to dry up in the spring, nor after the rains. There are a few exceptions to that that rule of thumb though, at least "Kaksi Tornia" boulder and the highballs on "Iso Kivi" are those to be mentioned.
During the summertime there are quite a lot of mosquitos, so don't forget to bring your repellent with you!
Please notice that the abseil rope on "Iso Kivi" is shorter nowadays, so you'll need to do a little downclimbing after topping those highballs climbed all the way to the top of the boulder. This has been done for security reasons in order to prevent kids living nearby climbing on top of the big boulder.
For all the First Ascentionists: Topo suggestions with silly eliminations and unnecessary variations will not be approved. Keep it simple and natural please!