Join us to make maps for humanitarian emergency use, using online satellite imagery and aerial photography, simply through a browser on your laptop.

There will be free very tasty nibbles, good coffee and other beverages (vegans no problem). There will be full instructions. There will be addictive map making.

You'll need:

* a laptop with any browser apart from Internet Explorer (you can download another in advance)

* ideally with a mouse

* to aim to arrive promptly to benefit from all the initial instructions (helpers will be on hand throughout the evening too)

* to book your place in advance at https://www.eventbrite.com/e/missing-maps-reading-mapathon-tickets-44751829928

To get an idea of the event and what it's all about, watch a short video

This is a joint #helpoften event organised by Reading tech groups and Sunday Assembly Reading.