What is the 'ETH' into which Albert Einstein enrolled?

ETH stands for: die Eidgenössische Technische Hochschule Zürich. It is also known as the Swiss Federal Polytechnic School (in) Zürich, Zürich Polytechnic, the Swiss Federal Institute of Technology in Zurich.

It was, and is, one of world's finest scientific schools, having graduated a great number of Nobel Prize winners, including Dr. Einstein.