Instructions
Go to the bomb shop in Ordon Village and buy a bag of bombs. Exit the village and head north to Hyrule Field. To the left, rocks will be blocking the path on the rock bridge. Use bombs to clear the path and go through it.
Jump across the small opening and climb the two ivy ladders leading to the top. Look to the southwest corner of the map where the path is blocked once again. Use your bombs to blow up the boulders. Keep going north and blow up more boulders. As you travel further along, shadow beings will prevent you from going back. Enter the Twilight where Link will turn into a wolf.
Keep moving along the narrow passage. You eventually catch the scent of one of the children named llia. Keep using Sense to follow the scent all the way to the open field. Take the southwestern path back to Hyrule Castle. Follow Ilia's scent all the way down to the castle gate. Go inside and eventually the scent will lead you to Telma's Bar where you'll find Ilia.
After the cut-scene, go to the back where soldiers are talking. Listen in, and find the location of Lake Hylia on the map at the table.
Leave the town the way you came in and head to the field. Take the Northeastern path, making your way down to the location of Lake Hylia. Run south and you will reach the Great Bridge of Hylia.