The Gartnerkofel is one of the three striking mountain peaks on the Carinthian Nassfeld ( http://www.nassfeld.at/ ) and a beautiful mountain tour for the whole family ( http://www.nassfeld.at/de/aktiv/familienberg/berg-familie ). With the starting point at the top station of the Gartnerkofel chairlift ( http://www.nassfeld.at/de/aktiv/wandern-und-biken/bergbahnen ), the Gartnerkofel hike is an easy summit tour. The ascent is a pleasant, even ascent, partly over the slopes of the ski area. The last stretch up to the summit cross requires a bit of fitness and head for heights. But there are no really exposed spots along the way.
Alternatively you can start at the state border at the Nassfeldpass or at the Watschiger Alm.