The phrase is:
mada minu kimi e tsudzuku. I believe the kana is:
見ぬ is the archaic/literary form of 見ない, the negative form of the verb 見る, to see/meet. So I think the whole sentence literally translates to "(Something: "the road" or something I guess) leads to you, whom I've not seen yet"
In most cases 'minu' translates to 'unseen'.
The full sentence まだ見ぬ君へ続く can be roughly translated to "(It) still continues unseen to you"