Yes, I've always wondered about this tunnel. The entrance doors to the tunnel is right next to the token booth at the 35th Street entrance in the Herald Sq station. On the East exit, there is a sign that says "BMT, 34th Street, Penn Station". If you ever walk on the East entrance of the Herald Sq station, you can def walk free from the Gap/34th Street to 35th Street / 6th. This is most likely part of the pathway. I doubt this pathway would be anything more than storage for the MTA. If connected and with Durst's plans for the BofA tower, you could potentially walk from 31st / 8th Ave to Herald Sq continue to Bryant Park and then with the new durst pathway, walk to Times Sq station and all the way back over to the 8th Ave / 42nd Street exit. Amazing. Wish it would come to life, would certainly help eliminate pedestrian traffic street level and separate the tourists from the office workers...