Lived in London 25 years, visited NYC often enough.
If you have a job in Central London, you have the option to live out south-west a way, and be in the birthplace of competitive running clubs: Wimbledon Common, Richmond Park, the river Thames towpath. Massive green spaces to enjoy on weekends or summer evenings. Hundreds of people to train with. Central London also has more green space in the middle than most cities, too.
You also have at least 20-30 clubs to choose from, races every weekend on XC in winter, track meetings maybe twice a week all summer, and a parkrun (free timed 5k, see
www.parkrun.com
) every Saturday morning in just about every park in the region.
It's grey and wet at times, and this year we have had precisely two hours of "snow". Less atmospheric than a "real winter" but better for running.
There is a reason all the Kenyans base themselves here for the summer ;-)