Royal Family's Tomb
The Royal Family's Tomb is located at the back of the graveyard in Kakariko Village. The only true reason to ever visit this area is to retrieve the Sun's Song.
When you get to this large tomb, play Zelda's Lullaby. The grave will break open, causing a hole to open in the ground, indicating there's something down below. Down there you will find some Keese, kill them to open the nearby door. In the next room there is a small congregation of three Redeads, they can easily be avoided. Once you get to the next room there is a headstone, read it to learn the Sun's Song. This song makes you able to skip to the night, or skip to the next day. This is very helpful, especially in Hyrule Field when the Stalchildren come out at night, mad skipping through the lush field.