There's a large bronze butt in the middle of this ancient city

I just thought you might like to know. In answer to your next question, yes, it's a butt on both sides.

Structure in another park 2, Oviedo

There are no plaques. It's in a park next to a monastery.

In the park in Oviedo

I don't know what this is. It's in the middle of the park. It has a stone base and nice woodwork and it's covered in graffiti.