Lampertheimer Altrhein, Nature reserve in Lampertheim, Germany.

Lampertheimer Altrhein is a nature reserve comprising wetlands, meadows, and forested sections along the Rhine in Hesse. Walking and observation paths allow visitors to move through the different habitats and observe the landscape's varied character.

Protection of the area began in 1937 to preserve river habitats and their natural systems along the Rhine. This early conservation effort established a foundation for long-term protection in the region.

The reserve serves as a local learning space where visitors come to observe birds and understand wetland ecosystems through direct experience. For many in the region, it represents an important connection to the natural history of the Rhine corridor.

The reserve is accessible on foot using clearly marked trails that accommodate different ability levels. Sturdy footwear and weather protection are advisable, as the ground can be wet depending on the season.

The Welsche Loch, a 40-hectare shallow lake, is named after Johann Welsch, a boatman from Nackenheim who in 1878–79 was the first to pass through the new Rhine cut near Lampertheim. The cut, planned by Johann Gottfried Tulla, severed the loop and created today's Altrhein. A cormorant colony lives at the lake.