Conglog : mineral : Slate | Conglog : years_connected : 1874-1920 | [TABLECONTEXT] : name : Conglog | Conglog : closed : 1920? | Conglog : opened : 1872 | [TABLECONTEXT] : [title] : List of quarries served by the Ffestiniog Railway
The Conglog quarry for slate mineral is opened in 1872 and closed in 1920 and is connected by the Ffestiniog Railway during 1874-1920