7-Mile Fen Thunderstorm © Joe Blastick/TNC

Location: Near the towns of Marvin and Summit in northeastern South Dakota  

Note: Additional information including directions will be provided upon registration.  

Description: See calcareous fens, an uncommon type of wetland that receives nutrients from cold and mineral-laden waters, on public and private land near the towns of Marvin and Summit, South Dakota. These wetlands, which are never flooded but always saturated, host rare calciphilic or "hard-water loving" plants. Please RSVP by Aug. 19 to the Conservancy’s Joe Blastick at