intiñan
Sunday. There is a second museum near the monument, Intiñan, which says its line is the real equator. It's closer. My Garmin still disagrees by a few dozen metres.
A young guide did the famous demonstration: a sink full of water with a leaf in it, moved a few metres north, then south, then onto the line. North it drains one way, south the other, on the line straight down.
It's a trick. The Coriolis effect is far too weak to decide which way a sink drains. It depends on how you pour the water in. I didn't say anything because the tourists were so happy, and the guide was very good at it.
Carmen bought a keychain. "One foot in each hemisphere," it says.