The Old Chateau is well-known for its housing of Rotom.
You can get there by grabbing a Pokemon with Cut out of your PC and go to Eterna City.
Go through the forest entrance and cut down the small trees blocking your path to the Chateau.
Rotom is on the second floor, in the middle TV. He will be level 15 when you catch him.
in eterna forest
In Pokemon platinum this pokémon would be Rotom. You find him in Old Chatau in Eterna Forest.
The Old Chatau is in the Eterna Forest. Go to the exit near Eterna City, and there will be two cuttable trees. Cut one down and move on forward. There, the house, is the Old Chatau, and you can catch Rotom here. To catch Rotom, you just have to go to a TV during a certain time (I forgot, I think it ends at 3:00am). If you fail to capture him, just defeat the Elite Four and Cynthia all over again and go back and try again. :) Hope it helped!
no its in eterna forest near the entrance to eterna city
Eterna Forest
the old chateau in diamond is in the eterna forest. fly to eterna city then go left to eterna forest. but you have to cut the trees before you could go in to the old chateau.
in eterna forest
its in the eterna forest.
It is in the Eterna Forest, near the Eterna City entrance.
it's between Eterna Forest and Eterna City
In Eterna Forest.
it is not in a city, its in eterna forest