A couple of things before you start the trail.

Firstly, books are a lot like cats. They are sleepy, mischievous and easily distracted.

If you type in an answer and a book does not light up, it’s possible that the book is napping, or distracted by something shiny. Give it a wave, head to the next one and it should light up for you.

The books can be lit up between 4pm and 10pm on week days, and 10am and 10pm on weekend.

When you are on site in Greenwich, and ready to start the trail, press the button below.

This will wake up the books, which will take up to five minutes.

If you are going to take more than 20 minutes between two stops, ring the bell again on the way.

(Model is Ragnar, the finest cat in London)