Planet Earth - Worlds within worlds?

Are there holes in the poles?. Is Earth hollow and resonates like that of a bell but beyond our sensory perception?. Much yet remains to be discovered. Outwardly we view and interrogate the realms of space in the search for a new life sustaining planetary surface but given relativity as to size what lies beneath our own feet?. Containment seemingly being infinite where do internals end and externals begin and what are they contained in?. As our Earths Poles shift upwards in not having to carry the burden of ice masses by how much will the oceans rise possibly leaving the poles a land of last resort.