I went to YELAGIRI with my colleagues on December 4th and 5th of December 2010.
Yelagiri is a small hill station. It's 225 Kms from Chennai. Though there is nothing much to say about this hill station, It is just a week end get away if we dont have any other option.
We stayed at Aurovalley resort in yelagiri. But, to say owner SALLY is a very nice person and they all gave their best to make our trip a pleasant one.
We also went for trekking on the second day (ofcourse.. dont expect huge, again its a small hill).
Again ... Its not a big hill station... just a ween end get away if no other choice.