Ther is some kind of climbing (and boulder) wall in Lahti University of Applied studies (Yrkeshögskolan) Faculty of Physical Activities, but as I know it is only for the educational activities and to students who have accomplished some kind of approval test (I think it´s the normal test where you have to proof that you know how to belay you fellow climber (with GriGri or/and ATC), make deasent figure of 8 and dress you harnes right.)
I propose that you contact local teacher Jyrki Hämäläinen to have more information about possibilites to go there. I think he´s email adres is something like jyrki.hamalainen (at) Lamk.fi.
There is also some kind of small climbing wall In Pajulahti sports center in the municipality of Nastola (www.pajulati.fi
), but it is open only for the groups, so you are not allowed to us it with out the local sports instructor.
I think there could be quite good markets to deasent indoor climbing wall if someone just would found it. We have in finnish scale 2 big sports academies / centers in the Lahti region ( Pajulahti sports center in Nastola and Vierumäki sports institute in Heinola), but so far they have not seen this opportunity. So nowadays the only possibility to access good indoor clmibing wall is to drive 100 km to Helsinki and go to Helsinki Climbing Centre in Tapanila (www.kiipeilykeskus.com