Saint Twrog's Church is in the village of Maentwrog in the Welsh county of Gwynedd, lying in the Vale of Ffestiniog, within the Snowdonia National Park.

When Twrog first arrived in the village, the valley would have been very marshy, which provided him with the wattle that he would have needed to build his cell.

The church that was on the site before 1896 was dedicated to Saint Mary, which has a connection to the Cistercian monks who were very numerous in the Maentwrog valley at one time.

He translated the metrical psalms into Welsh, and the present west window commemorates his work.

[4] The church was rebuilt in 1814 on the old foundations and was described as a neat stone edifice and was rectangular with a square embattled tower.

There is also a very old attractive church entrance gate which opens on the main road in Maentwrog.