Hexenstein, Glacial erratic near Lindau, Germany

Hexenstein is a gneiss boulder in Lake Constance, about 160 metres west of the Lindau railway embankment where it reaches the island. It is a glacial erratic from the last ice age, rising just above the water surface and marked with a red sign warning shipping of the shallows.

The Hexenstein is a glacial erratic of the Wasserburg-Lindau moraine, carried to its present spot during the last ice age. A second, smaller Hexenstein once stood near the Römerschanze by Lindau harbour; it appears on the 1822 cadastral map but is no longer visible. A 1902 book already called both stones erratic blocks.

The name comes from a local legend about a witch who supposedly used the stone to escape across the lake. This story continues to shape how people understand and talk about the place today.

The stone is visible from the shore and is best seen during low tide when it rises above the water. Visitors can observe it from the Lindau waterfront promenade without needing special equipment or travel.

A second, smaller Hexenstein once stood by the Römerschanze near Lindau harbour; it appears on the 1822 cadastral map but is absent from current maps and aerial photos, and would now lie inside the Römerbad.