Hakunila Boulder has many popular powerful routes and pumpy traverses. The rock quality is good enough and it dries quickly after the rain and early in the spring. The rock is easy to reach with both bus and car. The approach is short and easy. As a downside, the traffic noise is loud and summer days are likely a little too hot.
Most popular routes are Hanoi Rocks 7A+, Blade Runner 6C, and Naboo 6B. All three are greatly recommended. The rock has many traverses from 6B+ to 7B+ providing logical steps to improve your skills and endurance.
Block number 2 offers few easier but taller routes. It's worth to check either for warm up or training. It's in the shade at afternoons/evenings when the routes at the main block see scorching sun.
The Hakunila blocks are easy to spot when driving Kehä 3 and it's safe to assume that there's been climbers for a very long time. All the routes were presented already at the SKIL's 2003 red topo book, but some route names indicate that the active development took place around the year 2000.
The first topo book did not have any verbal instructions to any of routes. Only a hand drawn picture of the block with some lines on it. Also 27crags missed route infos for quite a long time. Some knew the original ways to climb the routes (from slouppi discussions or Lyseo Topos), but most did not. This resulted to another layer of routes with slightly different instructions added here. This topo should now have the original instructions for the routes.