Edinburgh Orienteering Series: Bonaly Multi-Cache

• Hillend Country Park
• Bonaly Country Park
• Blackford Hill and The Hermitage
• Corstorphine Hill
• Cammo Estate

Note that the last cache (Cammo Estate) is a bonus cache that can only be completed once you have done the other four!

Orienteering

Orienteering is a sport involving navigation between control points (controls) marked on a map. The challenge is deciding the best route between controls and trying to complete the course in the quickest possible time. Orienteering events take place most weekends if you are prepared to travel a bit. They range from small "come and try it" events held in local parks, right up to large multi-day events attracting 1000s of competitors from all over the world! Courses are usually set by age and ability, but smaller events may simply use colours to grade the courses (white, yellow, orange, green, blue ... etc). Either way there is usually a course for everyone.

More information can be obtained from The Scottish Orienteering Association or from one of the two Edinburgh-based orienteering clubs: Edinburgh Southern Orienteering Club and Interlopers. Or feel free to contact me via my profile!

Maps

You don't actually need proper maps to complete any of these caches, however if you would like detailed maps of the areas, you can buy them as follows:

• Hillend and Bonaly: Pentland Hills Regional Park Office at Boghall on the A702 during normal working hours (phone 0131 4453383 to check), or from the Hillend Ski Centre during its opening hours. The Bonaly map can (usually) be obtained at a slightly higher price from the Bonaly Corner Shop (corner of Bonaly Road and Bonaly Avenue). I say usually because when I checked, they had run out!
• Blackford Hill and The Hermitage, Corstorphine Hill and Cammo Estate: The Hermitage of Braid Visitor Centre or Cammo Lodge Visitor Centre, both normally open from 2-4pm on weekdays (phone 0131 4477145 to check)

Alternatively, maps can be obtained from Edinburgh Southern Orienteering Club, or contact me and I'll pass on more specific details of how to get them.

Compasses and Bearings

Unlike the cache at Hillend, parts of this cache require that you follow route descriptions, which may include distances and bearings. You will therefore need a compass and know how to use it. Personally I find a compass easier and more reliable than a GPS as its not dependent on satellite coverage.

Most compasses have a large baseplate with an arrow, a rotating housing with numbers and a magnetic pointer where the red end points north (unless the polarity has been reversed, which can happen if you put it through an xray machine!). Taking a bearing is pretty simple really:

• rotate the housing until the desired number (i.e. bearing) lines up with the baseplate arrow
• keeping the compass flat, turn around until the red magnetic pointer lines up with N (north) on the rotating housing (usually the housing itself has an arrow to make this easier)
• walk in the direction of the baseplate arrow, keeping the red magnetic pointer and N (north) on the housing aligned at all times

In orienteering, all bearings are magnetic as the maps used have north lines which point to magnetic north!

The Cache

This cache is at Bonaly Country Park and the co-ordinates above are your starting point, a gate just beyond the parking area.

The course I've set involves visiting the following controls in order: 26, 22, 25, 23, 28, 24, 30, 37, 35 and 39. At each control there will be a red and silver marker, usually attached to a post (see example). The marker will show the control number (26, 22, 25 ... etc) together with a single or double letter/code. Check that you've found the right one (using the control number), make a note of the letter(s) and then convert the "missing" one into a number using the formula A=1, B=2, ..., Z=26.

The following table describes the course:

You should now be out in the open, with good views over Edinburgh (and your GPS will probably start working again!). The cache is nearby, but first you need to calculate its location. As a sanity check, the numbers you have worked out should add up to 144.

The final cache can be found at the following co-ordinates:

N 55 53.ABC W 003 1D.EFG, where

A = (value calculated from the letter at) control 35
B = control 24 - control 37
C = (control 28 - control 39) - control 23
D = control 30 - control 22
E = control 25
F = control 26 - control 22
G = control 35

Please make sure you put the cache back exactly as you found it.

Bonus Cache

To get back to the car-park, continue by visiting the following controls in order: 21, 38 and 32. Again at each control, double check you've found the right one (using the control number), make a note of the letter(s) and then convert the "missing" one into a number using the formula A=1, B=2, ..., Z=26:

As a sanity check, the numbers you have worked out should add up to 36. These values are required to complete the bonus cache: Edinburgh Orienteering Series: Cammo.

Good luck!