Excavations in the 1960s at the site of the current Industrial Estate uncovered two large henge monuments and a series of hengiform pit circles from the late Neolithic period.

[2][3] Excavations in 2006 and 2007 at the Bryn Cegin site (extending the industrial estate) found an early Neolithic house and later, possibly Romano-British, settlement[4] In 1648 during the English Civil War the Battle of Y Dalar Hir was fought near Llandygai.

In the church is a marble monument to Archbishop John Williams, the Lord Keeper of the Great Seal during the reign of James I.

There is also monument by Richard Westmacott to the first Lord Penrhyn, in which the sarcophagus is flanked by a quarryman and peasant woman, described by Eric Hobsbawm as "the earliest sculpted proletarians".

[5] Shortly after her husband's death, the first Lady Penrhyn set up a school for girls in the village[5] in what is now Neuadd Talgai.

[15] The model village, within the loop of the former line of the A55 road, retains much of its original character, despite some more recent additions, having been declared a conservation area in 1974.

The correct Welsh language spelling is Llandygái, with the accent signifying that the last syllable is stressed as opposed to the last-but-one, the usual pattern.