Allt-fawr

Cwmorthin quarry was a slate quarry west of the village of Tanygrisiau, north Wales. Quarrying on the site started in 1810. In 1860 it was connected to the Ffestiniog Railway. In 1900 it was acquired by the nearby Oakeley quarry and the two were connected underground. In 1970 it closed along with Oakeley. There was small-scale working in the 1980s and 1990s, and the mine finally closed in 1997.

Moel Druman is a mountain in Snowdonia, North Wales and forms part of the Moelwynion. It is a subsidiary summit of Allt-fawr.

Wrysgan quarry was a slate quarry near the village of Tanygrisiau, Blaenau Festiniog, North Wales. It was worked intermittently from the 1830s, and was worked continuously from c.1850 until 1946. Wrysgan was an underground slate quarry, which was located on a small inaccessible site, some 1,390 feet (420 m) above sea level, to the west of Cwmorthin.

Nyth-y-Gigfran quarry (sometimes spelt: Nith-y-Gigfran or Nidd-y-Gigfran; sometimes known as Glan-y-Pwll quarry) was a slate quarry in the town of Blaenau Ffestiniog, North Wales. It was located about 300 feet (91 m) above the settlement of Glan y Pwll, south of what was to become Blaenau Ffestiniog. The quarry was sited on the steep cliffs that form the eastern edge of Allt-fawr and was entirely underground. The quarry opened around 1840 and became part of the Oakeley quarry in the 1880s; this in turn closed in 1969.

Conglog quarry was a small enterprise situated to the north-west of Tanygrisiau, near Blaenau Ffestiniog in Wales. It was overshadowed by the much bigger Rhosydd quarry a little further to the west. It was active from 1854 to 1910, and was operated by an individual, two partnerships and four separate companies over this period.

Deep Sleep is an underground hotel located in Wales. It is built 1,375 feet (419 m) below ground level, inside an abandoned mine in Cwmorthin quarry in Snowdonia (Eryri) National Park. It was opened in April 2023 and claims themselves as the deepest accommodation in the world. The mine where the hotel is located was abandoned and left to rot in the mid-twentieth century.

Oakeley quarry is a slate quarry in the town of Blaenau Ffestiniog, north Wales. It was the largest underground slate mine in the world, and had 26 floors spanning a vertical height of nearly 1,500 feet (460 m).

Dinas station was built by the Festiniog Railway (FR). It was the first passenger station in Blaenau Ffestiniog, then in Merionethshire, now in Gwynedd, Wales. This station is not to be confused with Dinas some miles distant on the Welsh Highland Railway; nor is it to be confused with the Festiniog and Blaenau Railway's northern terminus in the centre of Blaenau Ffestiniog which was sometimes referred to colloquially as "Dinas".

Ysgafell Wen is a subsidiary summit of Allt-fawr in Snowdonia, North Wales. It is the highest point on a broad ridge that stretches to the north-west of Moel Druman, and includes two other summits, Ysgafell Wen North Top. and Ysgafell Wen Far North Top.

Ysgafell Wen Far North Top is a top of Ysgafell Wen North Top in Snowdonia, North Wales. It lies directly to the west of Ysgafell Wen North Top, and rises as a rocky outcrop from one of the dog lakes, Llynnau'r Cwn.

Ysgafell Wen North Top is a peak on a ridge in Snowdonia, North Wales. It lies to the north of the highest summit on the ridge Ysgafell Wen. It is a subsidiary summit of Allt-fawr. The summit is located at the edge of Cwm Edno, an edge that falls steeply into the cwm. Small lakes surround the summit, known as Llynnau'r Cwn (the dog lakes). To the west lies the peak's top, known as Ysgafell Wen Far North Top.

Moel-yr-hydd is a subsidiary summit of Moelwyn Mawr in Snowdonia, North Wales and forms part of the Moelwynion. (Strictly the mountain is not actually in the Snowdonia National Park as it falls within the exclusion "hole" around the former slate town of Blaenau Ffestiniog.) The mountain overlooks the village of Tanygrisiau and Tanygrisiau railway station (a halt on the Ffestiniog Railway) from where the mountain can easily be ascended.From the 1830s until 1946, Wrysgan Quarry was worked on the north east flank of the mountain. Substantial underground chambers were driven beneath the summit.