The Milton Keynes Boundary Walk is a circular walk approximately 65 miles long around the boundary of the Milton Keynes Unitary Authority; it is waymarked with the Oakleaf symbol.

In 2012 a group a local geocachers divided the walk into sections and set a series of over 300 caches along the boundary.

More information about the walk and caches can be found at the website Caching the Boundary.

The magenta section of the walk is approximately 3.75 miles long and starts at the B526 north of Stoke Goldington. It passes through the village of Ravenstone and ends in Weston Underwood, near Olney. Most of the section is on public footpaths across agricultural land, with the exception of the Ravenstone and Weston Underwood, so be prepared for challenging conditions underfoot. The route is marked by footpath markers all the way across the fields, however these are sometimes obscured by the undergrowth.

There are 18 caches in this section (plus this Bonus) and each cache contains a letter to help you find the magenta bonus cache, which is hidden near the middle of the section. There are only seven different codes to find ( A, B, C, D, E, F & G ), so each one occurs at least 3 times in the series.

This one is a 1.50l clip-lock box.

To obtain the coordinates for this cache you need to obtain the seven different bonus codes which are spread across the 18 regular caches, then to find the final coordinates you've got to play the numbers game off Countdown (Do-do, do-do, diddly-do !). You should find you've got one from the top, and six from the bottom.

Calculate xxx = (D * E * (B-C)) + ( A * G )

Calculate yyy = (( C - F ) * ( B * A )) + ( D * E ) + ( G - E - A )

N 52^o 08.xxx W 000^o 45.yyy

This cache contains the Magenta Section Bonus Code required for the MKBW Golden Bonus (GC3RHQR)