Some might like to see a ships peg off a very old ship. If you look at the end you will see a wooden shive in the end. Not perfectly round and wider at the ends.
I have one similar that was used to connect logs ends together pike a pin. Has the same wedge that was used to "tighten" it into the holes through the logs.
It could be a fid. They're used to this day, including by myself, to splice lines (ropes) and other uses on ships. That one looks hand hewn so it is probably old.
That would be some big rope. Picture are that great. A fid these days has a point on it so as to push it threw the line for braiding and splicing incase others are wondering. It hallowed out so rope can slid thru main rope line by using the fid to open up the line..