When we were building our house, we installed an actual ground rod that the electrician connected--somewhere. I remember it being a literal rod getting pounded

When we were building our house, we installed an actual ground rod that the electrician connected--somewhere. I remember it being a literal rod getting pounded into the earth, pretty close to where we have the main power enter the house. The water pipes are not metal at our house, so they would be of no use as an electrical ground. This was in 2014, in Poland.