It is under the deep sea near the the enterance of Route 130/129
Underwater cavern.
Seafloor Cavern, just before you hit Route 129.
There are loads of legendary Pokemon in Sapphire, but if you mean the main one, Kyrogue, then it is the Underwater Cavern.
you will find team aqua in the under water cavern near the dive point in sootopolis
At sky piller. on the top floor is Rayquaza. - Mr. Seidschlag
The Adamant Orb can be found underwater in Route 128 on the Sealed Cavern when diving in the middle.
earthquake in Sapphire will be found in seafloor cavern in the room that you battle Archie of team aqua
There is no Pokemon mansion in sapphire.
He is not in Pokemon: Sapphire. You will not be able to find him. He is in Pokemon: Diamond, Pokemon: Pearl, and Pokemon: Platinum. You will definitely have trouble finding him in Pokemon: Sapphire.
you can't find it in Pokemon sapphire, but you can find it in Pokemon ruby. Hope this helped. :-)
You will find him in Magma Cavern and Southern Cavern.
After the underground cavern under the ocean go to sootopolis city and you can find kyogre in the cave of origin. Raquaza can be found at sky tower near pacifidlog after defeating the elite four.