I came back to finish this series this morning. I'd done the groundwork last week but sodded up the calculations. I had a Eureka moment and worked out how to solve the puzzles but realised that I'd got one number wrong. I was able to solve 5 of the 6 puzzles and the CO gave me the missing number and I was ready to roll.
I found all six caches in good time but it was still 4 miles for the full circuit! Luckily the rain held off although damp under foot.
The wall is a magnificent structure built during Queen Victoria's reign. If I owned the Braxted Estate, I'd employ a full time craftsman bricklayer and an apprentice to maintain the walls.
After I'd finished these puzzle caches, I picked up four trads around Tiptree to total 10 caches for the day.