Complex sentence: Since 1985, the GTA is propagated in the German speaking area of Werner Bätzing as an example of environmentally friendly tourism, in 1989 he brought out a guide, which is updated regularly since then.
Split into simpler sentences: Since 1985, the GTA is propagated in the German speaking area of Werner Bätzing as an example of environmentally friendly tourism in 1989. It brought out a guide, which is updated regularly since then.