The card shows a Steam Locomotive VLTJ No. 6 from 1910 with mix trains, on the Harboør station in April 1973.
If I had figured it out correctly, VLTJ stands for Vemb - Lemvig - Thyborøn Jernbane, or Lemvigbanen, which is a Danish railway line in Northwest Jutland. Established in 1879, the line extends from Vemb via Lemvig to Thyborøn. The single-track line is mostly level, and is operated with a fleet of five single-unit Y-train railcars.
The railway is to be used to test a prototype hydrogen-powered train in 2010
hydrogen-powered train...now that sounds cool!! If this hydrogen train poses questions, you can read more about it here
the stamp was issued this year (2010) and comes from a set of 8 stamps representing Denmark's nature. This stamp here shows a Natterjack Toad....uhmm, not something id like to cuddle...