Anglesey is close enough for a proper day trip from Llandudno, but large enough to expose poor planning. One cannot simply say Anglesey and assume the island will arrange itself around one’s lunch.

The island is reached via the Menai Strait, crossed either by Thomas Telford’s suspension bridge of 1826 or Robert Stephenson’s Britannia Bridge of 1850, both engineering achievements that still carry traffic across the strait with a confidence their builders would recognise.

It offers beaches, coastal villages, Beaumaris, ancient sites, lighthouses and wide views back towards the mountains. It is lower, broader and more open than Llandudno, with fewer Victorian manners and more sky.

The eastern side is easiest for a shorter trip: Beaumaris (with its concentric castle built from 1295 and considered the most technically perfect castle in Britain), Menai Bridge town and Penmon with its priory, dovecote and lighthouse. These can be covered in a half-day without rushing.

Longer days can reach Newborough Forest and beach (one of the finest and least-crowded beaches in North Wales), Rhosneigr for surfing and coastal walking, South Stack lighthouse on the clifftop above Holyhead, or the northern coast at Amlwch.

The standing stones, burial chambers and henges of Anglesey (including Bryn Celli Ddu, Barclodiad y Gawres and Din Lligwy) give the island a prehistoric depth that its modern roads and holiday traffic tend to obscure. These sites predate Llandudno’s Bronze Age copper mines and were ancient when the Great Orme was first being worked.

The island is not all polished postcard territory. Some places are plain, windswept or practical. That is part of the appeal. Not everything must flirt with visitors.

Anglesey looks compact on a map in the way families look simple in portraits. The road distances are manageable but the range of character (from the refined streets of Beaumaris to the Atlantic cliffs of South Stack) is larger than the geography suggests.

Go for space, coast, light and contrast. Llandudno is composed. Anglesey spreads itself out and asks what you intend to do with the horizon.

Allow a full day for any serious Anglesey exploration. A morning is enough for Beaumaris and the immediate eastern shore; the rest of the island rewards a longer commitment.