Fact One: There are three types of Welsh Iron Age Fort - and Garn Goch matches none of them.
According to an Oxford University survey in 2018, there are over 4,000 Iron Age hillforts in Britain, and Wales has a disproportionately large number of them – 687 if you really want to know - and there are essentially three types here in Wales.
Promontory forts along the coast make best use of high cliffs leaving only a narrow neck to be defended by banks, ditches, and the family or families who lived there. Today, they are usually called defended enclosures, and that’s a much more accurate term.
There are then the earthworks hillforts we’re all familiar with. Steep sided hills with consecutive lines of banks and ditches, and a relatively small flat area on top so there can be by fairly few defenders – let’s say a village-worth of people. But the key factor is very steep sided hills to make defending easier and attacking much harder.
Finally, we have the big stone-built forts. Usually built above cliffs with lots of ready made stone to help make huge, revetted – that’s to say smooth fronted – walls. This is Tre’r Ceiri on the Llyn Peninsula. Like nearby Garn Boduan, it had – and largely still has – 4 metre high, 3 metre wide walls with ramparts for soldiers to defend from, and sophisticated defended entrances.
Now, Garn Goch is more like these large stone-built forts, but not much like them. There is no way, for example, that there are anything like enough stones around Garn Goch to have once had walls 4 metres high and 3 metres thick, and there’s almost no steep sided hills, never mind cliffs.
So you ask, who said it was an Iron Age hillfort? See Fact Two.