After beating the Forest Temple, the gate behind Coro opens up. Once you go far enough east, you will find a wall of Twilight that you can enter to progress to Kakariko Village.
Ganon's tower is in hyrule past the barrier
Wind Waker takes place in the Great Sea, not Hyrule. Items are obtained from dungeons throughout the game.
Below the tower of gods its underwater. A note from Kanden: you can not explore the field. just the castle. but you do get the master sword
In the flooded Hyrule castle under the sea. However, you have to beat the first three temples before you're able to get there.
In most games his name is not mentioned. . .But in Wind Waker his name is stated to be King Daphnes Nohansen Hyrule.
Find all eight triforce pieces and return to Hyrule (find Tingle on Windfall).
When you get through the Tower of Gods.
No because hyrule is no longer submerged in water.
It depends on what game you are talking about. For example, in Wind Waker, Link was born on Outset Island, in Ocarina of Time, Link was born in Kokiri Forest while Zelda was (presumably) born in Hyrule Castle, in Twilight Princess, Link was born in Ordon Village while Zelda was born in Hyrule Castle, etc. The games never confirm any actual birth places.
There is the King of Hyrule a.k.a. Daphnes Nohansen Hyrule. I know that thanks to The Legend of Zelda the wind waker for the gamecube. There is also Ganondorf the king of evil and gerudos.
There is a character named 'Daphnes Nohansen Hyrule' as the last king of Hyrule kingdom from The Wind Waker. So Zelda's last name should be 'Hyrule' something. Usually CD-i Zelda series are not accounted in the Zelda World because it wasn't made by Nintendo.
Unless you go to the tower of gods and go to underwater hyrule there is no other way to walk under water.