Congress acted in 1872, appropriating
$40,000 for a lighthouse at Au Sable. The
State of Michigan sold 326 acres of land to
the federal government for the light station
at a cost of $407. Work began the following
year and continued into 1874. In late
July, 1874 the Light House Board released a
Notice to Mariners announcing, “Notice is
hereby given that on or about the night of
Wednesday the 19th day of August 1874 a
fixed white light will be exhibited from the
new brick tower at Big Sable Point…”
As was common for the U.S. Lighthouse Service,
the tower at Big Sable (the name was
changed to Au Sable in 1910) was not a
unique design. Built on the same plan as
the 1874 Outer Island Light in the Apostle
Islands of Wisconsin, its whitewashed walls
and black-trimmed tower made it an easily
noticed landmark.
“Notice is hereby given…”
The tower is 86 feet high measured from its
base to the rooftop ventilator ball. At its
base the walls are over four feet thick while
the wall at the lower lantern room is over
three feet thick. The tower foundation
consists of rubble masonary lying on bedrock
23 feet below the surface!

Cat Island is a barrier island off the Gulf Coast of the United States. The island is named for raccoons which early explorers mistook for cats.