Per https://wikitech.wikimedia.org/wiki/Maps/External_usage, please allow Wikimedia Maps to be used on wikidata.pl:

Link to site: https://mapa-zabytkow.wikidata.pl/
Purpose/details about your project: map with monuments, that allow upload files to Wiki Loves Monuments competition
Wikimedia Affiliate supporting project: Stowarzyszenie Wikimedia Polska