The Neutral Water Health Resort Sanitarium, also known as Dr. Smith's Sanitarium Site, is a historic site located at the junction of Claudius Street and London Avenue in Egg Harbor City in Atlantic County, New Jersey.

It was added to the National Register of Historic Places on March 20, 1991 for its significance in archaeology and health/medicine.

[3] The last remaining building is now known as the Roundhouse Museum, operated by the Egg Harbor City Historical Society.

[4] In 1905, Dr. Charles Smith built the Neutral Water Health Resort to treat patients with muscle problems.

Patients would soak and walk in the serpentine canal to get the benefits of cedar water.