The giant cauldron is spherical hole in the cliff. The hole might be something between few centimeters up to a few meters deep and wide. The giant's cauldrons usually have been formed after the latest Ice Age when glaciers melting water have rolled big stone or stones at its place. That curved many sized holes which usually are symmetric and have smooth wall. The stream has to be strong and tall enough to keep that drilling machine running and the waterfall have to be on its place long enough. It is possible that grinder stone is at the bottom of the cauldron but often it has been lost somewhere.
The giant's cauldrons of Pihlajamäki have found not early than 1995. They are the oldest cauldrons in Finland meaning something between 50 000 - 100 000 years old so they are formed before the last Ice Age. The diameter of the smaller cauldron is 1,6 meter and it is 3,2 meter deep and the bigger cauldron is 6,9 meter wide and it is 8,45 meter deep. Funny enough, finally it really seems that bigger giant's cauldron is the biggest one in Finland. Look the storyline below.
The place is easy to reach by public transportation. Take bus number 71 from the square of Helsinki railway station. It has a stop next to the cache. Or take commuter train "I" to Pukinmäki station and walk ~500 metres to the cache.
To claim this earthcache please attach on your log a photo of your GPSr at the cache site.
Please take care that your photo is easy to identify to taken at the site.
EDIT 10.1.2008!
Thanks to geoaware's claim I have to insert some stupid extra task here. So here we go. Calculate the volume of the biggest cauldron here and send your answer to me. Thanks! Voit logata tämän EC:n löydetyksi tämän jälkeen, eli hyväksymiskuittausta laskelmiin ei tarvitse jäädä odottamaan.
EDIT 19.4.2013!
Thanks to geoaware's claim taking the picture on the site is optional but highly approciated.
Just big or the biggest one?
Sorry, the most texts behind the links are written just in Finnish.
In early '90s when I visited first time the giant's cauldrons near Rovaniemi it was said that these are the biggest giant's cauldrons in Finland. Now I can not find any measurements to these cauldrons anywhere, perhaps you are luckier?
In Lapland there is also another big formation which is said to be the biggest giant's cauldron in Finland. More you search the information you able to find it is quite obvious that the way Pakasaivo - "Lapin Helvetti" (Lapland's Hell) is formed it is not the same as described early above on the text.
Surely we still have left one formation which is absolutely bigger and it is said to be the biggest giant's cauldron in Europe! But again, more you search available info it seems that Pirunpesä (Devil's Nest) is not formed as described early above on the text. If you like to have some nice geocaching also here, see this.
Well I am not a geologist I am just the geocacher.. Anyway it really seems that Pihlajamäki giant's cauldron is the biggest giant's cauldron in Finland!
Some extras
And to the happy end it is surely worth of reading "Helsingin kaupungin julkaisu - Kallioperän ja maaperän arvokkaat luontokohteet Helsingissä". There are listed every known giant's cauldrons in Helsinki and much more.