How deep can we go into earth's interior?

So far, the "Kola Superdeep Borehole" is the deepest artificial point on Earth.
Drilling began in the Pechengsky District of the old Soviet Union in May 1970,
and after 19 years, it reached 12,262 meters. (That's 40,230 feet, or about 7.6
miles.)  Although that was 25 years ago, nothing has been drilled deeper, and
it's still the record.

7.6 miles is something like 0.19 percent of the distance to the Earth's center.

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.

Ibelieve it's the pacific islands