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It tends to be the people in power who draw the lines on the maps.

Look at the straight borders that run across much of Africa,

drawn with rulers by bureaucrats and politicians,

which side of the line you fall determines how you're treated,

who represents you, whether you have a voice or even a home.

Worst of all is to be on no map at all.

Suddenly no one can hear you and no one knows what you need.

But what if we could all change the maps?

This is a programme about what you could call a mapping revolution

about citizen cartographers trying to reach the world's unmapped people and places.

Our story starts in Boston in the USA in January 2010 as the snow starts falling.

A new year at Tufts University in Boston for Patrick Meyer and Sabina Carlson-Robia.

So it was a late afternoon and I was in my dorm room.

I had just moved into a small apartment that my cousin's apartment.

Watching CNN in the background but doing some work.

And I was unpacking and actually listening to the BBC.

All of a sudden I see breaking news on CNN.

Little is over the radio breaking news.

Massive earthquake.

...