The village lies on the A496 between Harlech and Blaenau Ffestiniog, and also on the Roman road Sarn Helen, now classified as the B4410, at the junction with the A487 from Porthmadog, leading to the A470 (to Trawsfynydd and Dolgellau).
The National Gazetteer of Great Britain and Ireland (1868) stated that Tan-y-Bwlch was the postal town of Maentwrog.
According to legend, a giant known as Twrog hurled a boulder from the top of a hill down into the settlement, destroying a pagan altar.
[10] According to information in St Twrog's Church, based on a late addition to the Bonedd y Saint, there were four brothers and sons of Ithel Hael o Lydaw (Brittany) who came to Wales as Christian missionaries: The village settlement expanded in the 19th century to house workers from local slate mines.
[11] Within the village community is the imposing Plas Tan y Bwlch, home of the Snowdonia National Park Study Centre and former residence of the Oakeley family.