I believe that there are a few puzzles you have to complete. When you complete them, you will drop down, and see the Unknown.
There are two "caves" in the Ruins of Alph. The first is the Union Cave, which leads into the Ruins of Alph. The second is a series of caves which lead to the unown.
you first have to capture ALL the other unown letters
You can find it in the Ruins Of Alph which is south of Violet City.
look for all 26 kinds of unown then bring it to the staff in the ruins research center You can unlock some different unown each time that you complete a picture puzzle after you catch the 26 unown you can then catch the ! and the? in the hall of the Ruins Of Alph, and not with the others.
To catch Unown, you must go to the Ruins of Alph. Go inside of the ruins, and all the Pokemon inside are Unowns.
There is no place known as Unown Ruins, but you can find Unown in Solaceon Ruins in D/P/Pt and Ruins of Alph in HG/SS.
There are two "caves" in the Ruins of Alph. The first is the Union Cave, which leads into the Ruins of Alph. The second is a series of caves which lead to the unown.
in Pokemon heartgold ruins of alph in Pokemon soulsilver ruins of alph
after getting all the unowns at Ruins of Alph when you go in the Ruins of Alph a celebi comes
the solaceon ruins are an optional dungeon for catching the unown. just like the ruins of alph
go into the smaller ruins and slove the puzzels on the wall. The floor will open and you will fall into the ruins of alph. You will then find unown in the ruins.
you first have to capture ALL the other unown letters
go to the ruins of alph located in johto
You can find it in the Ruins Of Alph which is south of Violet City.
it turns into arceus NO IT DOESNT
In Platinum, Pearl and Diamond: Run around in the Solaceon Ruins In Heartgold and Soulsilver: Go to the ruins of alph, solve on of the puzzles in the rooms. They will open a trap door and you'll fall through it. When you run around in the ruins or alph a whole bunch of wild unown will appear
You can go through the Ruins of Alph without having to do anything; however, if you want to catch the Unown, you have to solve the 4 puzzles (of ancient fossil Pokemon).