2- There is a full heart container in a chest in the sanctuary.
3- Push the gravestone to reveal a hole that will take you back to the Hyrule castle sewers.
4- Heart piece cave, the cliff can only be accessed in the dark world.
5- Dash into the gravestone to reveal a staircase the leads to the magic cape.
6- Hyrule castle, which contains the boomerang, and the third possible spot for the lantern if you did not get it in Link's house or the area where you find your uncle.
7- The secret passage into the castle where you find your uncle and get the fighter's sword and shield. There is also the second possible chest with the lantern, if you didn't get it in Link's house.