A huge number of cities around the world remain unmapped. The Missing Maps Project wants to crowdsource digital maps of the entire globe.Despite massive advances in cartographic technology over the past decade, a huge number of large cities around the world remain digitally uncharted territories. Places from Dar es Salaam, Tanzania's largest city with a population of 4.4 million, to Dhaka, Bangladesh, with a population of 15 million, lack online street maps.