Six years ago today we launched https://openbenches.org/ - it is a crowdsourced map of memorial benches from around the world.
Uses OSM for displaying the maps and letting uploaders pick the exact right spot.
There's an API and data-dump so it can be incorporated into OSM - but our data isn't always as precise as needed. I'm still trying to work out a way to map an OSM bench ID to our ID.
If you're out mapping and spot a memorial bench, please do submit a geotagged photo to our site :-)