Bedrock Base Map Location 3
This distinctive granite crystalized from magma that formed nearly 1.5 billion years ago under a series of explosive volcanoes in central Wisconsin. The magma that fueled these volcanoes intruded into the overlying crust and formed large magma pools which slowly cooled and crystalized underground, forming large masses of granite that were later exposed by erosion. The brilliant pinkish-red hue of these rocks is due to the high percentage of the mineral feldspar they contain. Walk into the enclosed space and imagine you’re floating in a magma chamber miles beneath the surface of the Earth!