I went up the Dana Couloir once in July, and it was probably the most treacherous exposed thing I've ever done. I took several others who, like myself, were not very familiar with ice axe and crampon use, but we made it up without incident. Looking back, it was extremely dangerous -- because all the snow had melted off, so it was down to really hard ice. We each had crampons and a single ice axe. No rope protection, no anchors, nothing. A single slip could have been deadly.
Googling Dana Couloir brings up lots of pictures, and most of them show people climbing and making tracks in decent snow. But then there are a few showing double ice axes and blue ice. I think my climb was made in conditions somewhere in between.
Please be careful!
