Ha-Ha Wall

[cbg]

How should a Ha-Ha wall be marked on an O Map ... and why? Assume that it will be approached from both directions.

(In case of assistance required: http://en.wikipedia.org/wiki/Ha-ha)

[Barny of Blandford]

Try gully on the assumption that it is below ground level looking at the picture you link to

However I have seen some that I would mark as a wall as there is no ditch - just a vertical drop from a higher level lawn to a lower level farmers field

What does your example look like

[King Penguin]

Small crossable cliff ?, as walls usually have 2 sides.

[graeme]

At WOC they mapped a similar drop-off as an uncrossable wall. LOTS of people crossed it. I've also seen one which had barbed wire along (below) it mapped as a fence - I jumped off it (never saw the fence) and should have got DQed since all fences were OOB in that event.

I'm not impressed with a map which shows a visible feature which you can't in fact see. So I'd use a crag.

[Roger]

Crag.

My latest bit of remapping included changing a short length of retaining wall on a hillside into a crag: same logic.

[smf]

Small Crag

ESOC have a map of Hopetoun House (http://www.esoc.routegadget.co.uk/cgi-bin/reitti.cgi?act=map&id=14&kieli=) Where the mapper has used a row of small crags (to the east of the house).

[Red Adder]

I would suggest a small crag (to decribe the wall and possibly a form line - for the ditch that is generally bewond the wall.

The only one I have encountered whist mapping (for a 1:5000 map) just has a wide ditch (mapped with formline) and, a one point, a short section of balustrade above the ditch (mapped as a short wall). The latter has been used as a feature at an event with no complaints.

[pete.owens]

There was one marked as a crossable wall (ISSOM) half way up the run-in at the elite sprint champs at Astley Park last year.
http://www.sroc.routegadget.co.uk/cgi-b ... =87&kieli=

In ISOM have seen some mappers create a special symbol with only half the blobs showing, but that tends to be difficult to read. I have also seen a symbol with half blobs on ones side and tags on the other for a case where there is a fence running along the top.

[cbg]

Thanks for the replies. I wanted you all to say 'crag', as I find that one really expects to see something above ground level if there is an 'uncrossable wall' symbol on the map. It often occurs at the business end of rifle ranges (the butts), which would be best shown as a linear crag between higher and lower ground.

[Adrian]

Here's the ha-ha at Himley: http://reentrant.files.wordpress.com/20 ... ley-42.jpg