Latitude -32.213872, Longitude 150.45904
Located in the Upper Hunter Region of NSW, nearest town Merriwa
You can see an outstanding example of near horizontal columnar jointing at Battery Hill picnic area.
This is an amazing example of polygonal basalt columns also known as columnar jointing. The columns are nearly horizontal (not like those at Bald Hill Falls which are vertical). Around 35 million years old the basalt lava erupted at a temperature estimated to be about 1,200 degrees. The jointing is caused by shrinkage as the lava slowly cools; normally columns like these are vertical as the lava cools from top to bottom when the flow of lava is horizontal. In this case the flow must have been nearly vertical and the flow has cooled from the outside face causing the jointing to form inwards from the outer face in a near horizontal plane.
Battery Hill picnic area is 15 kilometres east of Merriwa and 8.5km west of Gungal. Proceed to the end of the picnic area road and look at the rock on the northern side. There is a picnic table and toilets at the site and a small reedy creek passes nearby so be on the lookout for and avoid venomous snakes whilst exploring this location.