Beginning on July 15, 1892, a fixed red light was displayed from a lantern hung from a tree on the American side of the St. Croix River, near Calais, to serve local navigation. The 1894 annual report of the Lighthouse Board explained the rationale for the light:
A light was needed at this place to enable the steamers, plying between Eastport and Calais, and especially towboats, to make the difficult turn at the Narrows, a few hundred yards above Whitlock’s Mill. The Canadian Government maintains two lights on the left or Canadian bank of the river, and another light was needed on the right or American bank to make the navigation safe at this difficult turn.
By 1902, the light was displayed from a post. A proper lighthouse and keeper’s dwelling were finally constructed in 1909–10. The lighthouse is named for a local man, Colin C. Whitlock, who tended the lantern that preceded it. Whitlock also owned a mill nearby, hence the name “Whitlock’s Mill.” Local legend has it that his wife often had to tend the light, as Whitlock was said to drink to excess on many an evening.
The interior of the 25-foot-tall lighthouse is lined with white ceramic-faced brick, a distinction shared with very few lighthouses. The tower was painted red until 1914, when it was changed to white. The L-shaped, one-and-one-half story, wood-frame dwelling, about 100 feet from the tower, has seven rooms. A small oil house was built about 300 feet from the lighthouse.
The light was automated in 1969. In the 1970s, the station was leased to the Washington County Vocational Technical Institute. Under the Maine Lights Program, ownership of the lighthouse was transferred to the St. Croix Historical Society in 1998.
The keeper’s house and other buildings are privately owned. The property was last sold in the fall of 2004. A 1931 pyramidal wooden fog bell tower also survives at the site; the bell from the station is now on display at the St. Croix Historical Society.
The lighthouse remains an active aid to navigation and now runs on solar power.
Directions: The lighthouse can be viewed from the St. Croix River View Rest Area on Route 1 in Calais. The rest area, which is about five miles North of the “Saint Croix Historical Site”, is announced by a "Rest Area 1,500 ft" sign from the south. At present, the lighthouse grounds are not open to the public. Believe me I know! I tried to seek permission from the resident of the keepers house to photograph the light, the house, the bell tower, and the oil shed only to be told that she didn’t think the two rather large, very protective dogs accompanying her would let me get out of my car. She made no offer to contain them and gave no directions from where I might shoot some photos. (I'll bet she is from "away"). However, after a bit of wandering, I found the rest area where I took the above photo.