The Light on Turtle Rock was constructed in 1887 by Frank Thurwanger, costing under $3,000 to complete, including a roofed shelter without walls surrounding the lighthouse tower.
It was constructed on Turtle Rock, a protrusion of rock on the east bank of the river just at the far end of Boathouse Row. 
For the bustling navigators at the turn of the century, the lighthouse marked a bend in the river, and was close to a dam erected in 1820 downriver, that stretched more than 1,200 feet across the river and (until 1950) included locks and a canal. The dam prevented tidal water from traveling any farther up river. Above the dam was fresh water, and below the dam stayed the brackish water. Above the dam the river current reached a calmness that greatly benefited the boathouses, rowing and all sorts of river activity. (citation http://www.workshopoftheworld.com/fairmount_park/dam.html )
When the city approved Sedgeley Club’s construction in 1902, they deeded the lighthouse to its members. The clubhouse was to be built surrounding the lighthouse, and thus the Light on Turtle Rock became part of Sedgeley Club’s boathouse. The only entrance into the lighthouse remains on the outside of the clubhouse. There is no access into the lighthouse tower from within Sedgeley Club. However, peeking into Sedgeley Club’s basement, you’ll find the base of the lighthouse tower, measuring 115 inches in diameter at the widest part. It passes up through the basement, into a circular alcove above called the Tower Room. The alcove is just about filled by the lighthouse tower. Remnants of the tower’s arched exterior windows, now filed in with brick, can be seen where the tower meets the floor on this level. Following the tower one story higher, you reach an outdoor porch with the tower in the center, surrounded by a low balcony. Here the tower rises until the octagonal walkway around the lantern room is reached. The two arched windows of the tower are found about half way up – one faces down river and one faces up river. The windows are delicately paned in a diamond pattern, and outlined in contrasting brick. Through these windows daylight enters the tower’s interior, illuminating the rungs for the tricky climb straight up. At the top of the lighthouse, hexagonal windows provided for the beacon are capped by a copper roof.
A peek inside the lighthouse tower today reveals a cement ramp which travels up and around the center for one complete spiral. Then a ladder, leaning into the tower’s wall is the only way up, followed a bit higher by rungs imbedded in the brick wall.
The shining beacon was originally a gas lit lantern. Later, a revolving lamp was powered by electricity and was only lit when the ladies of Sedgeley Club were hosting an event. In the past few decades, the lighthouse has been illuminated every night along with the beautifully outlined boathouses of Boathouse Row.
In 1987 at the 100 year anniversary of the lighthouse’s construction, a restoration campaign was conducted by the women of Sedgeley Club. The goal was to raise the $41,900 estimated for repairs and restoration of the lighthouse.
By 1990 the last check needed was written by a Sedgeley Club Member and Past President who is still active today, and is a current Board Member of Friends of Historic Sedgeley. From cleaning and repointing the brick, to rebuilding the old tower balcony, and replacing the gas lantern …work was underway. We had reached our goal and lit the Light on Turtle Rock for another 100 years.
For more information on the Light at Turtle Rock, see www.lighthousedigest.com, www.lighthousefriends.com and www.sedgeleyclub.org .