General Roy's Baseline (Southeast End) Cannon Monument

There's a cannon sitting on the Thames Path near Walton-on-Thames that marks something rather specific - the baseline used by General Roy to measure distances across southern England back in the 18th century. It's not flashy. It's not going to take your breath away. But if you're into the hidden history of how Britain mapped itself, it's genuinely interesting.

General Roy was obsessed with precision. In 1784, he and his team used this very spot as a starting point for a baseline measurement that would become the foundation for accurate surveying across the south. The cannon monument itself is modest - the sort of thing you could easily walk past without noticing - but the story behind it matters if you care about how maps actually get made.

Walking the Thames Path between Walton-on-Thames and the monument is pleasant enough, with river views and decent paths. You're not looking at this as a standalone destination; you go because you're already exploring the area. History enthusiasts and anyone interested in cartography or 18th-century engineering will find it worthwhile. Kids might struggle to get excited about it though - there's no interactive element, just a cannon and a plaque.

Combine it with time at Walton on Thames Camping and Caravanning Club Site if you're staying locally, or use it as a walking break if you're exploring the Thames Path properly. Allow 20 minutes, maybe 30 if you're reading everything carefully. Go on a clear day when you might actually see across the river properly.