I always thought that mapophilia was a lonely affliction until I started my blog, Strange Maps, in 2006. I remember the first map I posted – it was a map of the location of asylums for the insane in Pennsylvania. It provided a bizarre geography of insanity, and it interested me because it was not the kind of map that would have a place in mainstream cartography. Equally, the map didn’t tell us much about mental health. I loved it because it was such an interesting juxtaposition of a condition that is so difficult to define with something as cool, rational and delineated as cartography.

I’d find strange maps online – I don’t draw my own – and then categorise them, describe them and link them to other maps. I have more obvious categories such as history, science and tech, and politics, as well as unusual ones: love, sex and happiness, life and death, truth and justice. One type is the allegorical map. In the 19th century, symbolic maps were very popular, especially during prohibition in America. Prohibitionists would draw moral maps. They’d describe the country of drunkenness and how to travel from it to the continent of sobriety. The road to success was drawn across chasms of despondency and mountains of procrastination.

After a few weeks, I had thousands of hits. By the end of the year, I’d had half a million hits. Having thought that I was the only person who was obsessed with maps, I realised I was not alone.