I guess I found the only hill around London. It’s in Greenwich and 1675 they put the Royal Greenwich Observatory on top of it. And yes, that’s the home of the prime Meridian. A nice historical place where you can easily stand in the east and hold a cup of coffee in the west.

What they don’t tell you is that you are standing at the old prime meridian. Tue to a modern reference system the new prime meridian is about 100m east of the steel engraved, laser marked one.
I have been there too and found a squirrel.

After that I went DownTown extreme shopping for the rest of the day.