Nice work finishing (or nearly finishing) Vermilion County!

We can leave it for now. I'll take a look again when it re-grows.

These are paths through the prairie. Won't the footpaths be clear again when the prairie grows back?

I think you are making people nervous with these mass deletions of abandoned railroads. Some of these may be subject to rails-to-trails projects in the future so my preference has been to keep them if the way hasn't been built over yet. I don't really see what benefit there is to aggressively removing them since they generally aren't rendered anyway.

There seems to be conflicting information. The 2022 TIGER overlay labels it Kingsley Court, but McLean county GIS calls it Kingsley Street.
https://mcleangis.maps.arcgis.com/apps/webappviewer/index.html?id=541971ad75f248c38c9bc6ffcd3a7516

Yeah, seems like the nature preserve portion seems to be called Allerton Natural Area. Making that a separate area seems reasonable. The wikipedia page and this book (https://www.google.com/books/edition/Inside_Allerton/uZziAQAACAAJ?hl=es) call it Robert Allerton Park. Perhaps the Park & Retreat center just refers to the central area and Robert Allerton Park refers to the whole area. Or maybe they updated the name.

If you think this warrants it feel free to re-add it. I've mostly seen (and used) boundary=protected on state parks and similar areas under some kind of statutory protection.

That's a fair point. I've changed it to a pedestrian area and mapped the entrances.

Part of the structure rises above the ground and is visible from the street.

https://www.google.com/maps/@40.1070059,-88.2224079,3a,75y,359.87h,87.62t/data=!3m6!1e1!3m4!1sPMAmOKnyosL19RS0RZjquQ!2e0!7i16384!8i8192?entry=ttu

Why is that the case? They might not be mapped as buildings but I would think they could be mappable as nodes or areas.

This one is actually only partially underground so I think it should still be mapped as a building.

Usually they are mapped as landuse=grass and/or landcover=grass, so what you mapped is fine.

Are both bodies of water really called Sears Lake?

The regional planning commission maps it as a shared-use path so that document is likely incorrect. I haven't seen any other source that restricts it to pedestrian use. https://ccrpc.org/wp-content/uploads/2015/02/greenways-2014-plan-plan-only.pdf

I'm not certain The Boneyard Greenway is actually a cycleway. This pdf https://humanresources.illinois.edu/assets/docs/iWalk-Toolkit/boneyard.pdf claims it is intended only for pedestrian traffic. I mapped it as a path with bicycle=yes for that reason.

Thanks for contributing!

You can do this by drawing a line tracing the interior, holding shift while selecting the interior line and the exterior line, and then right clicking and selecting the "+" icon to merge the two lines into a relation.

At least as far as I can tell from the satellite imagery.

They plan to extend Hershey eventually, but I know what you mean.

Would these waterways be better tagged as streams?

Welcome to OpenStreetMap! I think historical performances at venues may be outside of the scope of OSM though.