Over halfway through your journey, you still don’t feel any closer to finding the eleventh destination. It doesn’t feel like you have enough information yet, but something is nagging at you… something you’ve missed?

To take your mind off it, you decide to visit the sights of old Istanbul, including the super Basilica Cistern.

Amid the cooling waters, you’re reminded of a puzzle you once saw…

You have two empty jugs, one with 6 litre capacity, the other 13 litre capacity. The jugs are irregularly shaped and have no markings for partial measurements. You have an unlimited supply of water, but no way to measure the flow. In how many steps can you get exactly 7 litres of water into the large jug.

A step counts as one of three things:

Filling a jug with water

Transferring water from one jug to another

Emptying a jug

For reference, the most famous version of this puzzle needs just 8 moves.