I did the New York marathon in 2007.
Hadn't been to NYC before or attempted a marathon so when the opportunity came along it seemed like a good idea to grasp it.
I didn't really follow any structured training programme beyond doing 3 progressively harder weeks in row with the 4th week being an easy week. The marathon was early November and I had not run a step until mid to late August having been training for and competing in the TransRockies that same year. My fist training run of 20mins left me almost unable to walk the next day!
My only regret was not training properly and tailoring the training towards a more ambitious finishing time. I was aiming for 4 hours and ended up completing it in 3hrs35 so with hindsight I would have trained to go sub 3hrs 30.
I was in proper clip at the end and was very glad indeed to finish.
The atmosphere was phenomenal though. The entire route (less the bridges) was lined with people at least 2 rows deep with 20+ live bands of all descriptions along the way.
Enduring memory was hearing a spectator shout:
[Brooklyn Accent]"Welcome to Brooklyn. Nobody quits in Brooklyn"[/Brooklyn Accent]