My Archery skill is at level 80 and I'm looking for Niruin, in Riften, to give me some training.

Where can I find him?

I'm no thief but Archery has nothing to do with Thief Guild.

I tried Ragged Flagon and waited without success.

Thanks for your help.

He is a thief and a member of the Thieves Guild. You have to be a member to get to him I believe. He only hangs out in the Ragged Flagon-Cistern.

See the passage just at the back of the Ragged Flagon bar on the right, go down there and turn right before the door, past the broom and the bucket.

I'm just in front of the door. It says requires a key.

It's really a nonsense to become a thief to get training in archery...

I have never been a thief and will not start it yet. OK then I'll go train myself with my 2 trolls. I didn't want to use that glitch too much but now, really, I'm so mad that I feel not ashamed in using it until 100.

What is funny, is that someone in Ragged Flagon has proposed me some training in Sneak. LOL.

Have you been to Angi's Camp yet? I think you can get five levels from her.

Yes I did it but only 3 rounds. I wanted to return for the last one after level 90 but now it doesn't matter. I just took 5 Sneak training with Delvin Mallory in the Ragged Flagon. I see that he is a Master of the Thieves Guild, like Niruin. But he trains anyone at least. What I don't understand is that in UESP wiki they don't mention that he trains only thieves in Archery...

There are quite a lot of small details missing over there, I'm sure they will included it... eventually.

This door is opened by Mercer or Brynjolf (can't remember which) once you join the Guild and stays open from then on. And once you gain access to the Cistern, you'll be able to use the shortcut in the side yard to the right of the Temple of Mara.

You may not want to join the guild but there is much to be gained by joining. Lots of benefits.

Thanks guys for those informations.

I prefer not to be part of the Thiefs Guild. I like role playing in a good way and I wouldn't feel happy playing as a thief. Even in Morrowind and Oblivion I excluded that Guild. But I know that I'm loosing some advantages. Like for the Civil War, I prefered to stay neutral.