The 'ridges and swales' were formed over 1,200 years as Lake Michigan’s water levels gradually receded, leaving behind sequential sand dunes.
The sanctuary is home to 26 of the roughly 50 orchid species native to Wisconsin.
The Range Lights consist of two separate towers; the front light is a small shed-like structure, while the rear light is a taller, permanent tower.
It was designated a National Natural Landmark in 1967 due to its high concentration of boreal and northern forest species in a southern location.
The sanctuary is one of the few places in the world where the Hine’s emerald dragonfly can breed, due to the specific dolomite-fed swale water chemistry.
The Ridges Sanctuary is Wisconsin’s oldest private nature preserve, established in 1937 to protect the sensitive habitats of the Door Peninsula. The landscape features a series of 30 distinct, parallel post-glacial sand ridges and swales that create a unique microclimate for diverse flora. This topographically complex environment supports one of the highest concentrations of native orchid species in the Great Lakes region. The sanctuary covers over 1,600 acres and includes miles of elevated wooden boardwalks that protect the fragile ecosystem from foot traffic. It serves as a critical nesting area for migratory birds and provides a habitat for the federally endangered Hine’s emerald dragonfly. The sanctuary grounds also house the historic Range Lights, which were constructed in 1869 to guide ships into Baileys Harbor. Visitors can explore the interpretive center, which provides educational exhibits regarding the local geological formation and botanical diversity.
The elevated boardwalk overlooking the central swale with the historic Range Lights in the background.
Bring insect repellent during early summer months to manage populations of black flies and mosquitoes in the swales.
Check the online bloom calendar before visiting to time your trip with the peak flowering season of rare orchids.
Stay on the designated boardwalks to prevent damaging the extremely fragile soil and plant life.
Do not attempt to hike through the swales or off-trail areas, as the vegetation is extremely sensitive to trampling and is prone to waterlogging.
The nature center and specific trails may have modified accessibility during deep winter snow conditions; boardwalks remain open for snowshoeing.
No pets, no foraging, and stay on marked trails to protect sensitive habitat.
