A really well designed course that utilizes the landscape beautifully.
Pro-level difficulty but still playable for beginners.
Excellent long par 4's and 5.
Well placed OB's.
Very challenging but totally fair and really fun.
You need both distance and accuracy as well as disc maneuver skill shots to do well here.
Great spot to improve your game and a genuinely enjoyable experience.

Generally great infrastructure but a few tees on the back 9 seemed a bit short.

Holes 11 and 15 are my favorites. 11 is particularly impressive for the stunning view, beautiful rock green, and the fun challenge of throwing off the edge of a cliff.

Signs at tees very detailed, way-point signs to holes, disc-return bin and information board by parking lot and practice disk. There also interesting incline and decline approaches on some holes along with a few roll and thumber challenges. Easy access to course using public transportation.

The map is wrong for hole 2. More than a few holes overlap one another and cross pedestrian paths, so some small design issues. In addition, holes 9 and 10 are fun, but a bit too dangerous, especially in wet conditions.

Overall, it is a very good local course. If you like the Meilahti course in Helsinki, the forest holes at Lauste, or Mukkulan in Lahti then try this course. I would not recommend the course in wet conditions, at least not holes 9, 10, and 16. I think the tee pad and sign for hole 2 is straight ahead of hole 1 basket, but I went by the map (It seems the basket was moved behind the hill where hole 3 starts). Course maintenance is good given the conditions there, e.g. the course is a bit too spread out and some sharp declines and tall vegetation can make disc recovery difficult. The parcel of land by the parking lot where hole 3 tee and hole 18 basket is located could have a few more holes for incline, decline, sharp angles, and challenging OB zones (would also allow for the baskets to be alternated for different game play each month), but those just suggestions. From Kerava station, you can take bus 5 to the last stop (Ratsastuskoulu, horse riding school), and then walk that same road until it ends; the sign to the park and turn off is straight ahead. There's no bathroom or water source on-site, and plan on the course taking about 1.5 to 2 hours.

UPDATE: DGCK (Disc Golf Club Keinukallio) has started to maintain this course, and it's now 18 holes instead of 9.

The people in the club have made an amazing job, built stairs for easier access to some holes, tore down trees, carved very nice new holes in the midst of a thick forest. Marked OB's, built fences, cut the grass so the fairways are nice and clean, set up trash cans etc. etc. etc.

Nowadays this is a really nice course and well worth a visit.

- The course is built on an old abandoned downhill ski resort, a rather small one, but there are a lot of height differences, which makes it more interesting

- Beginner friendly for the most part, but has two more difficult par 4 holes and also couple of hard par 3s. Has enough challenge to be worth a visit for the more advanced disc golfers.

- Has one really sweet hole, #7 is from almost the top of the ski hill, and about 105m (345 feet) downhill, the basket is in an area surrounded by trees, and you need to find a route to enter this area. Either a long tunnel shot, or a tight S-flex, or maybe even go over the top with a hyzer / anhyzer to land in the "jail"

- Lot of the holes give out many options on how to get to the basket, some holes are definitely easier for backhand players, but at least half of the holes give a proper forehand route too.

- The scenery is really nice, and as the course has a lot of elevation, it also gives a proper exercise every time too. Just remember to pack enough water with you!

- There are some holes that are adjacent to very high vegetation, so if you stray off the fairway it might be a lengthy session to find the disc.

- There might be some snakes on some of the holes, but to me they seemed to be non-poisonous ones (I'm no nature expert though, but we only have one poisonous snake variety in Finland)

Even when the course was updated to 18 holes and improved significantly there's still not too many golfers around to call the place crowded, so that's very nice.