Located between Marathon and Neys Provincial Park, Port Coldwell was once a fishing and shipping port. My dad says he remembers seeing some buildings still standing and being used in the late 60's. Today there is a cemetery which is still maintained, building foundations, dock, junked boats, and various scrap wood and equipment lying around the entire bay. There is also a huge partially sunken ship across the bay (you can see it clearly on google earth) which would be easily accessible by boat.
This is an excellent place to check out on a nice summer day and launch a boat from, especially if you are camping at the Neys campground near by.