Greenwich

On Thursday Sim and I checked out of the hostel, but left our stuff there for the day. We were catching a train to Paris that evening and didn't want to carry bags around all day. The plan was to visit Greenwich and maybe some other places before leaving town.
Greenwich as you may or may not know is home to the Prime Meridian which is like the equator, but for longitude. It is completely arbitrary in terms of location, but since the British empire controlled the world and the seas several centuries ago they got to pick where it went. There is also a Maritime museum at Greenwich which was pretty cool (at least to a nerd like me). There were some amazing models of ships that had incredible detail. Lots of hands-on exhibits too. Also in the observatory at Greenwich, there is an exhibit about the history of navigating at sea (part of the reason the Prime Meridian was created in the first place). It was interesting to see the process by which sailors learned to navigate out in the open ocean for months at a time. It is apparently fairly easy to determine latitude, but determining longitude was not as easy of a nut to crack. This problem was worked on by many of the great minds of the day and all of their inventions for calculating longitude and keeping accurate time can be seen here. I thought it was cool.