Nearly five percent of the people – close to one million – in Central Java, Indonesia, are illiterate. It is here that Ridwan Sururi, a 43-year-old professional horse-groomer, has set up a unique library. There is no membership fee but books aren't given out forever. They must be returned before another is borrowed. More or less like a perfectly normal library.

Except it's done on horseback. The library was started in 2015 with help from Luna, one of the horses under his care, and a donation of around 100 books from a friend. Sururi travels through the province with his horse, taking books to people that do not have access to them. The 43-year-old hopes to set up a permanent library near his house one day, so people can have more access to books.

India has its own version, although it's a little more mechanised and might have more miles under its belt.

In 2014, rural journalist P Sainath discovered what he called "one of the loneliest of libraries" in Kerala's Idukki district, that had a collection of around 160 books, all of them classics. Membership is Rs 25, plus a monthly fee of Rs 2 and free tea is provided to all.

The video below profiles a unique "residential library" in the Rocky Mountains in the US. It has a collection of over 32,000 books on natural history.