Nearby are the popular attractions of Sychnant Pass and Mynydd y Dref, and the town also lies partly within Snowdonia National Park (Eryri).

The bay is sheltered by the south-east tip of Anglesey and Puffin Island to the north-west and the limestone headland of Pen-y-Gogarth (the Great Orme) to the north-east.

The beach is extensive, consisting of smooth pebbles and a wide expanse of sand; it was awarded a Blue Flag for five years running.

In the west, the bulk of Penmaen Mawr lies between the town neighbouring Llanfairfechan and the wider coastal plain extending to Bangor.

The rounded hill of Foel Lys, Gwddw Glas (Green Gorge), Bryn Derwydd and the head of Cwm Graiglwyd and finally Penmaenmawr.

The coastal plain is nearly divided by Trwyn-yr-Wylfa, which also marks the boundary between Pant-yr-afon and Penmaenan in the west and the Hen Bentra or "Old Village" of Dwygyfylchi and Capelulo in the east.

The first, Afon Pabwyr, runs down from wooded Cwm Graiglwyd then under the town centre, Pant-yr-afon, to the beach; the second and larger, Afon Gyrrach, runs for about 4 miles (6.4 km) from the northern slopes of Tal-y-Fan to the sea near Penmaenbach, passing through Nant Ddaear-y-llwynog (The Fairy Glen) and the old villages of Dwygyfylchi and Capelulo.

There is evidence that axes from Graiglwyd were exported widely 5,000 years ago, examples having been found as far afield as Cornwall and south-east England.

The summit area was crowned by Braich-y-Dinas, one of the largest Iron Age hillforts in Europe, comparable with Tre'r Ceiri near Trefor on the Llŷn peninsula.

The quarried stone was lowered by self-acting inclines to the 3-foot (910 mm) gauge tramway which ran to jetties from where the setts were loaded into ships.

Ships continued to load cargoes from the Darbishire jetty until 1976, although sea trade had been sparse since the famous stranding of the Rethi Muller in 1967.

Railway ballast continued to move in quantity from the sidings near the station, but all the original infrastructure was swept away by the building of the new A55 Expressway in the late 1980s.

The town grew in popularity as a seaside resort for the well-to-do in the second half of the 19th century, in part due to the enthusiasm shown by statesman and Prime Minister William Ewart Gladstone who holidayed eleven times in Penmaenmawr between 1855 and 1896.

[11] On 27 August 1950 the 1:45 am up-express passenger train from Holyhead to Euston, the Irish Mail, was approaching Penmaenmawr station at 60–70 mph after passing a distant signal set to "clear".

A Saturday service X2 has been introduced by Padarn Bus that runs direct between Penmaenmawr and Llandudno eastbound, and to Llanberis via Bangor westbound.