Water End Swallow Holes

Water End Swallow Holes is a geological site in Welham Green comprising fifteen natural sinkholes formed within the chalk bedrock across approximately 11.3 hectares. These depressions developed through the natural drainage of groundwater in this water-permeable landscape.

The site received protection as a Site of Special Scientific Interest in 1986 due to its geological and biological value. The chalk sinkholes themselves formed through natural hydrological processes that have operated over many centuries.

These limestone formations serve as an educational resource for scientists and researchers studying the natural drainage systems of southeastern England.

Access to the site is provided via Station Road and is managed by Welwyn Hatfield District Council. Visitors should wear sturdy footwear as the ground is uneven and can become slippery in wet conditions.

The area contains Reed Sweet-grass populations in its deeper water sections alongside a willow carr swamp system. These two distinct habitat types coexist in close proximity and support different ecological communities.

GPS coordinates: 51.72390,-0.22064

Latest update: December 13, 2025 17:08