No you cannot get on Neptune Drive from the trolley trail and that metal fence that they put up there to prevent that is still there and apparently that area is all private roads. Was just there. The trolley right of way goes on however, along a dirt/grass right of right and comes out at a road called Haley Crescent which is still- possibly part of the private enclave. This way is basically a narrow strip of dirt path that was not only completely passable, but surprisingly dry for me after a rainy spell. (was on my Surly Long Haul Trucker with 28s) The obstacles are that fore mentioned gate which I do not recall having any problem with, and a big rock that required slowing up for or dismounting and walking around. Not exactly sure of land status the end, but I am sure that if any of it was private land, that they would have put have up the same "keep out" signs that line the right of way.