Locating deleted items

When you know where data is amiss you can use use Overpass Turbo to display the data of that region at a certain date or between two dates.

To do so you go to the place where you miss the data (zoom in as far as possible to minimize the server load), paste the query of your desire at the left side and click "Run".

To restore data you can either click on the data you look for and use the changeset or way/node ID for an undeletion in JOSM with reverter or undelete plugin. Or you try some of the possibilities "export" offers (although only "raw data" worked for me while testing it now.

(I tried to paste the queries here but they aren't shown, thus just the link.)

If you forget both the location and id, there's still a tedious way. Download the full-history file and search for the item with your item's name (or any tags). If the item has the condition of "visible=false", then it's deleted.

But remember, this is the last resort.

You can use Potlatch 1 to look for deleted ways in an area. There isn't an easy way of looking for deleted nodes.

If someone's deleted something and replaced it with something else then you can of course look for nodes that were deleted in the changeset that added the new thing, but with large changesets that'll be a challenge.

The answer that is now at the top guided me in the right direction when I now had this problem (was wondering why there was no building on the map where I remember one being in reality), but may be confusing to some people; it certainly was for me.

Overpass Turbo is indeed the right tool for this job. A query that finds historical data there looks something like this:

[out:json][timeout:25];
retro ('2022-01-01T00:00:00Z') {
// gather results
(
  nwr["building"]({{bbox}});
);
// print results
out body;
>;
out skel qt;
}

Adjust the date in the retro line depending on when, and in the nwr["building"] line depending on what you are looking for.

When you have found a date when it still existed, it will display the deleted object on the map, which you can click and will get a link to an ordinary openstreetmap.org/way/... link which you can click and find the changeset that deleted it.