The closest place to Shenzen that is outside of the restricted area. Used to be used by the British military for listening/watching as well as for exercises.
Can be reached via roads or more interestingly by a short hike from Ho Sheung Heung.
Some old pictures: http://www.4regtra-reunion.org.uk/16005.html
Some new pictures: http://www.tripntale.com/trip/4839/ho-sheung-heung-hong-kong-20080106-t…