Contact us

Got a question, spotted a mistake on a map or in our data, or have an idea for a new tool? Write to us here. We read every message.

How we reply

We read every message. If you leave your email, we’ll reply ourselves, with no automated answers.

We can’t promise a timeframe, because it depends on how many messages come in. Without an email we can’t reply, but we still read it.

Your email stays private

We only use it to reply to you: it’s never published or shared, and we won’t add you to any mailing list.

We don’t publish ours either, to keep it free of spam. That’s why everything comes through this form.

What we do with your data

Before you write

Methodology and sources: where each elevation, coordinate and boundary comes from, and how accurate it is.
Corrections: the mistakes we’ve fixed, with their dates.
There are no accounts: what the tools save (like a list of addresses) stays in your browser only. If you clear it, we don’t have a copy.

Maps for class

Our blank maps, worksheets and quizzes are free for class and personal use: print them and hand them out without asking. If you publish them, credit the source shown on each map. For anything else, choose “Using our maps or data”.

Printable blank maps