From Festipedia, hosted by the FR Heritage Group

Within the environs of the railway, there are 2 distinct locations known as Dinas. These appear near opposite ends, not only in time but in location.

The first to appear was Dinas in the area above Glanypwll, near Blaenau Ffestiniog, and the original terminus for the Festiniog Railway. Hereafter it is referred as Dinas Branch

Today, however, there is a location some 20 miles away on the Welsh Highland line, which is also called Dinas . Hereafter it is referred as Dinas Junction

The first location had ceased to be a station, a number of years before the latter was constructed.