Exciting things in the woods

Year 2 have been in the woods this morning. It wasn’t an ordinary day though. We were investigating some things that had been found on the nearby building site. The staff at the museum in town had brought the things into our woods during the holidays so that the builders could carry on. This morning we had a look to see what these special finds were before the museum came to collect them so that we could use the woods again.

I wonder if you can guess what these things could have been? They were very old and had been under the ground.