Reviving an old idea Use pencil for "speedy reaction".
Originally intended as a puzzle to solve during long winter evenings, but well...it's spring already, go figure!
It's not that easy to find available space in Vlissingen, if -like me- you haven't solved/found most mystery or multi-caches in the area yet. However, after a few trials and many errors, I did manage to find a nice place; well, nice... The hide itself is nothing to write home about, nor is the container, just a black bison. Nonetheless, the general area is quite pleasant: dunes, beach, sea, a couple other caches...
Enough yap yap, on with the puzzle!
Here's two sets of numbers for you, the first one is for the columns, or vertical, or North-South. And the other is for the rows, or horizontal, or West-East. You need to combine those to get something to work with.
7127/112111/13111131/13113131/131111131/111211/71117/1/112155/41413/142211/142/213433/43/73111/11641/1311222/1311223/1312331/1132/7431
7117/113111/1311131/13121131/1311131/113111/71117/11/541112/11143/131344/211101/41111/115/7145/1172/1311341/131115/1312212/11511/72121
For all numbers use the single digits, except for the one bold 10 which is actually 10 (ten).
You could use (graph) paper, a pen and a big bottle of correction fluid. Or a few pencils and erasers. You could, but you shouldn't. Really, you shouldn't. You will make mistakes, many mistakes, use a spreadsheet instead, it's much easier to make corrections. You will also need logic to get to grips with what you're seeing. And you will need a (modern) mobile phone, although there are other means to extract the coordinates. And finally time, you need time, lots of it.
There is absolutely no doubt about the coordinates when you have solved the puzzle.