The historic site at Jelling (a World Heritage Site) consists of two large burial mounds with a small church between. The slightly smaller south mound is just visible in this picture behind the church. The famous runestones are outside the south porch of the church (not visible in this picture, but see the next tip and the Jelling page for pictures of these).
On the other side of the stone, there's a Runic inscription reading "King Harold the Blue Tooth introducted Christianism"
On the major Runic Stone there's the first image of Christ found in Denmark. It's amazing how good it has been preserved after more than one thousand years.