Dag Holtan-Hartwig (born April 16, 1991), known professionally as Slopes, is a Norwegian singer, composer and music producer.

[1] Holtan-Hartwig grew up in a musical family in a suburb of Oslo and began playing in bands at the age of twelve.

At LIPA, he met fellow Norwegian singer Halvor Folstad and started to work with him.

Folstad returned to Oslo, and Holtan-Hartwig worked as a producer in London and later in Los Angeles.

Returning to Oslo, Holtan-Hartwig and Folstad formed the duo Skinny Days[2] in 2015 and released their debut single Alright Right Now.