Tal-y-llyn: the art of glaciation

Tal-y-llyn Lake, also known as Talyllyn Lake, Llyn Mwyngil or Llyn Myngul is a large glacial ribbon lake formed by a post-glacial massive landslip damming up the glaciated valley

How deep is the Mawddach Estuary?

According to my tame geology expert, the Mawddach estuary is not an estuary at all but a fjord carved out by the glacier and then filled with sand and sea as the ice melted and retreated.

But how deep is this estuary/fjord?

I certainly can’t say, but perhaps the prospectors of rich minerals who have drilled here over the years could tell us….