Functionally, they are pretty much walls - like walls could be high brick walls, very low stone walls around churches or cemeteries, or remaining walls of a collapsed building. Seems reasonably accurate :)
No infoboard, the name is most likely a description (but it seems good to keep as-is for now).
Status/future of the objects themselves isn't very clear either: https://zinas.tv3.lv/latvija/apzinot-padomju-laikus-slavinosas-pieminas-zimes-nereti-saskaras-ar-sarezgijumiem/ .