The community boundary encompasses the areas of Penrhyn-coch, Salem, Pen-bont Rhydybeddau, Cwmsymlog, Cwmerfyn, Banc-y-darren, Cefn-llwyd, and Capel Madog.
The boundary runs along the Nant Clarach for a short distance before climbing through Gogerddan forest, then along the middle below Broncastellan Fort, until reaching the road from Bow Street to Pont-goch.
It is at the east, over Garn Bank near Caer Pen y Castell, where the community reaches its highest elevation of 437m above sea level, just north of the summit.
The boundary passes through a forest owned by Natural Resources Wales until reaching the shore of Syfydrin Lake at the eastern end of the community.
There it heads south across the moorland until it reaches Ponterwyd Road just west of the Buwch a'r Llo (Cow and Calf) Standing Stones.
The border leaves the Pen-llwyn road just before reaching Capel Dewi, and follows the Peithyll River through the small wood of Pwll Crwn to the edge of Pont Rhyd-hir.
Unusual plants and lichens grow on these sites, consisting of species which can tolerate high levels of metals in the ground.
Natural Resources Wales has installed car parks and footpaths in the forests at Gogerddan and Round Pond.
The earliest traces found were in a pit, and included burnt grain, indicating the presence of farming nearby.
In 1923 a quartz standing stone was moved from Fanc Troed-rhiw-seiri to the village square to serve as a memorial to the dead of the First World War.
[14] The ring barrow near the original site of the standing stones was excavated in 1955, finding an Early Bronze Age grave, and a Roman cremation.
When Lewis Morris came to Cwmsymlog in the mid-18th century, he reported seeing the remains of an old mining method at Twll-y-Mwyn, Cwmsebon, and stone tools that he claimed had belonged to prehistoric miners.
[14] Since the late 20th century a number of Bronze Age ore mines in Wales have been discovered by new archaeological works, most of them at Elenydd.
In 2005 additional stone hammers were found on the edge of the Twllymwyn works, along with other evidence which confirms that mining took place there in the Bronze Age.
[19] Sarn Helen crosses Trefeurig on the road between the Roman forts of Penllwyn on the banks of the Rheidol, through the Middle Peninsula and past the Courtyard, to Talybont.
During the Norman invasion of northern Ceredigion in the early 12th century, Ystrad Peithyll Castle (Grid Ref SN623824) was built, and a wooden tower was placed on top of a mound surrounded with a ditch.
Parish council oversight included road repairs, preserving old shafts left open when the mines were closed and supplying clean water to residents.