As someone who runs something similar, but for stained glass I'm going to go against the grain here and commend you on your data set. I think a lot of posters here are unfamiliar with how time consuming gathering these datapoints can be. It's mostly by hand, mostly by randomly searching or scrolling through Wikipedia, stumbling upon a partial data set, or physically traveling and having first hand knowledge that a place exists. How were you able to put together such a GREAT dataset?
You could add the facility for visitors to add their own locations or submit them for review. That way the people who "know something is missing" can add it themselves.
You could add the facility for visitors to add their own locations or submit them for review. That way the people who "know something is missing" can add it themselves.