When you ask a question be sure you follow the basic rules;
- Use correct grammar and make sure the reader can understand what you want answered.
To enter the Denerim Alienage you'll have to bring Arl Eamon to Denerim. There a maid called Erlina will asks for your help in saving Queen Anora from Arl Howe.
When you're done with the quest, the Denerim Alienage will open up to you.