@ci_lantro That’s what we were thinking. Luckily it doesn’t smell. Not sure what to do with it though as it’s a pretty solid pipe

It's not supposed to smell! It would be worth $2-300 to me to have it gone so I would call a plumber. I would remove the baseboard and paneling and then call the plumber. They should be able to open up the wall and cut the fitting off , adapt to PVC and get it square with the wall and install an inconspicuous cover.

Or maybe even have the plug on the exterior of the house (if the bathroom is on the ground floor which it probably isn't.)

Does it have a proper cover? It kind of looks like something was just stuffed in there. If that’s the case, then it requires attention. :)

@ci_lantro Hm okay, good idea good idea.

The bathroom is on the ground floor, if that changes anything

@Sammy No it doesn’t. The previous owner nailed two pieces of wood over it, and had toilet paper stuff into it for some reason. We just assumed it was a pipe to nothing after they renovated the bathroom the first time. But it may be worth calling a plumber at this point

I would certainly want to make sure. You dont need sewer gas coming in. You say it doesnt smell, so it could be disconnected, but, then it should have been removed. Have it checked out. Much better to be safe than sorry. The little shelf was probably a cover up to sell the house.

Might have been an old sink drain except that seems an odd place for a bathroom sink. Any reason to think this room might have been the kitchen originally?

May well be an abandoned line.

Thinking out loud here....the pipe almost had to go through the wall to the exterior, didn't it? Because it is sitting right over the foundation?

From the looks of it, it almost has to be a waste pipe. It looks like maybe 2-3" internal diameter. That'd be too small for a wall mounted toilet, but way larger than I'd expect for a sink.

Cleanout seems like the most reasonable guess, though I don't recall ever seeing one in a bathroom of an old house. I wonder if there's an abandoned soil stack going up through that wall.

It's a puzzle for sure.

It like a stack to me that is no longer in use but you will need to open up the wall to tell for sure and I am wondering why you didn’ t do that in the beginning of the reno since now you have to deal with a bit more mess.

Maybe a drain for a washing machine once upon a time?