Seven Mobile telephones have installed in several stones which is installed in two places.
In the Hirasawa-Kanga ruins there are five stones and five telephones, and there is one stone and two telephones in the Tukuba Central park. I installed several music in each telephone, and each calling music springs up from the ground in each environment when you call the number of telephone. It is a inter-live concert.
It is free, because none answer only you make music.

A term of telephone performs :
  The 6th October 2007 - The 11th November 2007. (Japanese time)
  This project has installed the mobile telephone with the cooperation of KDDI.