On a high, eroding bluff along Lake Michigan, Two Creeks is an ancient forest of pine, hemlock, and spruce that became established about 12,000 years ago. During various glacial advances and retreats, water, silt, and clay buried the forest, and over time constant wave action exposed the soil layers, uncovering long-buried branches, logs, and tree stumps. Radiocarbon dating provides a precise glacial record and evidence of boreal forest development in the Two Creeks area.