Characteristics of a good winch site

Lots of interest in another thread from US readers in looking for good
winch sites. I thought it might be useful for those of us from countries
where winching is common to give our list of essential and desirable
characteristics for a good winch site.

From my UK experience I'd say there are two essentials:

1. A long enough run to consistently achieve launches (nil wind) of 1500
ft or more. For 10 years I was a member of a club where on a nil wind
day one would do well to get 1300 ft. That's the difference between a
thermal-finding ratio of 80% and around 60%, which makes a huge
difference to soaring pilots. That suggests to me a cable run of around
4,000 ft.

2. Enough space so that gliders waiting to be launched can remain
gridded without being in the way of those landing. The club above has
only a narrow runway, so that gliders waiting to be launched need to be
pushed off every time someone comes in to land. This often made
launching frustrating. For safety this suggests a wide field, at least
at both ends.

A nearby flat land club has both these characteristics and is very
successfully winch only.

As desirables I'd add some hilly bits to help with thermal generation,
but these are not essential, and that grass is kinder to winch cables
(though waterlogging can reduce use of the field, so perhaps a hard
track to run the cable retrieve vehicle would be good) and is the only
surface on which retrieve winches seem to be workable.

Finally, if the site is next to a ridge I'm far more comfortable if the
field is at the foot of the ridge, rather than on top, because landing
back at the field should be possible if the ridge is unworkable.