Ffynnon Llugwy

Pen yr Helgi Du (Head or Hill of the Black Hound) is a mountain peak in the eastern part of the Carneddau in Snowdonia, Wales. It lies on the south-eastern flanks of Carnedd Llewelyn, and is linked to Carnedd Llewelyn over the col of Bwlch Eryl Farchog, a knife-edge ridge over the cliffs of Craig Yr Ysfa. From here the walker can drop down into Cwm Eigiau to the east or to the Ffynnon Llugwy reservoir to the south. Continuing over Pen yr Helgi Du to the east you will reach the even more beautifully named Pen Llithrig y Wrach (the slippery peak of the witch).

Llyn Llyffant is the highest lake in Wales, located at grid reference SH 687 645. Its name translates into English as "frog lake". It lies at an elevation of approximately 815m above sea level.

Carnedd Llewelyn, also spelled Carnedd Llywelyn, is a mountain massif in the Carneddau range in Snowdonia, north-west Wales. It is the highest point of the Carneddau and the second highest peak by relative height in Wales, 49th in the British Isles and lies on the border between Gwynedd and Conwy.

Llyn Melynllyn (Welsh for yellow lake) is a lake within the Carneddau range of mountains in Snowdonia, North Wales. It lies at a height of just over 2,000 feet (610 m), and has an area of some 18.5 acres (75,000 m2). Cliffs rise steeply from its western edge, up to the summit of Foel Grach, and down from which most of its feeder streams flow. A small dam was built at its northern end in 1887, but this was deliberately breached in 1970. The lake acts as a reservoir for the Llandudno area. Less than a kilometre to its north lies the larger Llyn Dulyn. The outflow from the lake is called Afon Melynllyn, this stream flowing north-east to join Afon Dulyn, itself a tributary of the river Conwy.

Foel Grach is a mountain in the Carneddau range. It is the eighth-highest summit in Snowdonia as well as Wales, and is included in the Welsh 3000s. It is located on a broad ridge extending northwards from Carnedd Llewelyn to Carnedd Gwenllian (formerly Y Garnedd Uchaf) and Foel-fras. An emergency refuge has been built below the summit. Compared to the surrounding mountains, much deeper snow settles here due to its rather broad summit and high grassy slopes. On clear days the Isle of Man and even the Mourne Mountains in Northern Ireland can be seen from the summit.

Pen Llithrig y Wrach is a mountain peak in Snowdonia, Wales. It is one of the four Marilyns that make up the Carneddau range. To the east is Creigiau Gleision, another Marilyn, while to the west is Pen yr Helgi Du and Carnedd Llewelyn. Craig Eigiau and Llyn Eigiau can be seen to the north, while Gallt yr Ogof, Glyder Fach and Tryfan can be viewed to the south. It has one of the more colourful names of any British mountain, translating as slippery peak of the witch, perhaps in reference to the boggy conditions underfoot, or because of the resemblance of its pointed profile to an archetypal witch's hat. It is an outlier of the Carneddau, the higher peaks of which can be reached from Pen Llithrig y Wrach via Pen yr Helgi Du. On its eastern side, the mountain slopes steeply down to Llyn Cowlyd. It may be climbed from the southern side, from Capel Curig or the A5, or from the north-east, from Dolgarrog or Tal-y-bont in the Conwy valley. It is quite prominent when viewed from the north near Llandudno.

Llyn Dulyn (Welsh: black lake) is a lake on the edge of the Carneddau range of mountains in Snowdonia, North Wales. The lake is 33 acres (130,000 m2) in extent and 189 feet (58 metres) deep. Less than a kilometre to its south lies the smaller Llyn Melynllyn. Cliffs rise steeply from the lake edge up to the summits of Garnedd Uchaf and Foel Grach, giving it a dark brooding appearance - hence its name. The lake was dammed in 1881, to increase its capacity, and was significantly altered in 1931 by Llandudno Waterworks.As a reservoir Dulyn (along with Melynllyn) provided water for the town of Llandudno. The reservoir was repurposed in 1997 for use as hydroelectric generation. The outflow from the lake, the Afon Dulyn, also feeds water into neighbouring Llyn Eigiau. Afon Dulyn flows north-east, passing Tal-y-bont before joining the River Conwy. The cwm has been the site of a number of aeroplane crashes including that of an American Dakota aircraft which crashed into the cliffs above the lake in 1944 killing all four crew.

Yr Elen is a mountain in the Carneddau range in Snowdonia, Wales. It is the ninth highest mountain in Snowdonia. The average annual temperature of the peak is around 4 °C (39 °F). It lies on a short ridge running north-northwest off the main northeast-to-southwest ridge of the Carneddau, just over one kilometre from Carnedd Llewelyn. It is usually climbed from the main ridge of the Carneddau, as it is only a short walk from Carnedd Llywelyn. It can also be climbed from Gerlan, near Bethesda, following Afon Llafar then heading up the slopes of Yr Elen, but this involves walking through wet valleys and a number of rivers that are difficult to cross. In drier times, ascent can be made via the crossing of Afon Caseg and then up the "front edge" of the peak. The views from this point north-west, over to Bangor and Anglesey, are stunning on a clear day, especially with a summer's sunset. This is well worth the arduous ascent. The etymology of the name is unclear, with the personal name "Helen" or "Eleanor" being one possibility, perhaps after Eleanor de Montfort (d. 1282), Princess of Wales and wife of Llywelyn ap Gruffudd. Another is the leech (from soft mutation of Welsh gelen, leech), perhaps in reference to the way in which Yr Elen appears to be attached to the side of the remaining Carneddau.

Gyrn Wigau is a summit of the Carneddau range in Snowdonia, Wales, and forms a part of the western Carneddau commonly known as the Beras. It is a top of Drosgl. It has only 15 metres of topographical prominence but is listed as a Nuttall.

Carnedd Gwenllian (named Y Garnedd Uchaf before 2009) is a minor summit of the Carneddau range in Snowdonia, Wales, and included in the Welsh 3000s. From the summit, distant views to the north can extend as far as Ireland and the Isle of Man, and to the South as far as the Berwyn Ranges. It lies between Foel Fras and Foel Grach, but is not always included in the Welsh 3000s, as its summit rises only slightly above the ridge. However, it is classed as a Hewitt. Its slopes, like all those in the northern Carneddau, are largely grassy, although they are steep. The slopes can receive significant accumulations of snow-drifts during blizzards in winter. In the past, snow beds have survived on the mountain as far as June. The annual average temperature on Y Garnedd Uchaf is relatively cold, ranging between 4-5 degrees Celsius.For some years there was a campaign by the Princess Gwenllian Society to have the name of this peak changed from Y Garnedd Uchaf to Carnedd Gwenllian. Gwenllian of Wales (1282–1337) was the only daughter of Llywelyn ap Gruffudd. After her father's death, she was held in a nunnery at Sempringham in Lincolnshire until she died. In September 2009, the summit was renamed Carnedd Gwenllian, and the Ordnance Survey agreed to use the dual name Carnedd Uchaf/Carnedd Gwenllian on its maps from 2010 onwards.

Y Drosgl is a summit of the Carneddau range in Snowdonia, Wales, and forms a part of the western Carneddau, also known as the Berau, meaning 'stacks' or 'ricks'. It lies on a ridge heading west from Carnedd Gwenllian and Bera Mawr towards Bethesda. A large ancient burial cairn, dating from the Bronze Age, adorns the summit, from where good views of Cwm Caseg and the Menai can be seen.

Gallt yr Ogof is a mountain in Snowdonia, North Wales. It is a subsidiary top of Glyder Fawr, and is the most easterly point in the Glyderau mountain range, not including the hill Cefn y Capel. Gallt yr Ogof is 763 metres high.It is a sister peak to Y Foel Goch, which is located on the ridge heading west to Glyder Fach. As its name suggests there is a cave to be found on the cliffs on the precipitous eastern side of the peak.