Before you could get round Mirkwood in the North you would be right among the slopes of the Grey Mountains, and they are simply stiff with goblins, hobgoblins, and rest of the worst description. Before you could get round it in the South, you would get into the land of the Necromancer; and even you. Bilbo, won’t need me to tell you tales of that black sorcerer. I don’t advise you to go anywhere near the places overlooked by his dark tower! Stick to the forest-track, keep your spirits up, hope for the best, and with a tremendous slice of luck you may come out one day and see the Long Marshes lying below you, and beyond them, high in the East, the Lonely Mountain where dear old Smaug lives, though I hope he is not expecting you.