Location: Grächen, Switzerland
Website : https://www.ultratourmonterosa.com/
Ultra Tour Monte Rosa is a 100 mile / 170 km ultra trail race along a classic European long distance footpath, the Tour de Monte Rosa. The race route leads anticlockwise around the Monte Rosa massif, so it is similar to the UTMB, just a bit harder.
Damo Hall says it well: https://twitter.com/Ultra_Damo/status/1215246160165818374