Riot: How far is Summoner's rift from Mt.Targon?

Taric says he can see his mountain from the rift when he buys a ward. How far is it away?

Now I know what you all are thinking, "The rift has nothing to do with the lore." and let me tell you that you are somewhat incorrect. What goes on in game doesn't impact the lore, but the setting still has some importance since the river that flows through it was followed by a group of gypsies that descends from (I'm paraphrasing, but I remember Jareden saying something about that).

So please tell us Riot, how far is the Rift to Mt. Targon? And is summoners rift the rift in which much of the void is seeping out of? Is this why Baron Nashor is a big threat?