Henry Ernest Dudeney/Modern Puzzles/165 - The Despatch-Rider in Flanders

Modern Puzzles by Henry Ernest Dudeney: $165$

A despatch-rider on horseback, somewhere in Flanders, had to ride with all possible speed from $A$ to $B$.

The distances are marked on the map.

Now, he can ride just twice as as fast over the soft turf (the shaded bit) as he can ride over the loose sand.

Can you show what is the quickest possible route for him to take?

This is just one of those practical problems with which the soldier is faced from day to day when on active service.

Important results may hang on the rider taking the right or the wrong route.

Which way would you have gone?

Of course, the turf and the sand extend for miles to the right and the left with the same respective depths of three miles and two miles,

so there is no trick in the puzzle.

1926: Henry Ernest Dudeney: Modern Puzzles ... (previous) ... (next): Unicursal and Route Problems: $165$. -- The Despatch-Rider in Flanders
1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Geometrical Problems: Solid Geometry Puzzles: $311$. The Dispatch Rider in Flanders