This template can be placed on region articles that have specific listings listed that should be moved to city articles. Usually, this template is placed at the at the bottom of an article that contains listings that should be moved. The template should indicate which article sections require clean up.
This website uses the Wikivoyage API to get and display all the information you see. This is the MediaWiki API, which is a general API for accessing data from Wikimedia projects. You can find information about it here: MediaWiki API.