A disaster has befallen the good ship CityMetric: our staff writer Barbara Speed, who has been with us since before we even launched in July 2014, is leaving us. She’s moving on to take up an exciting new job as comment editor of the the i newspaper. This, then, is my last chance to make her talk about the various silly stories I've made her look into over the last two years: think of it as a sort of Barbara Speed greatest hits compilation. In it, we shall attempt to answer the following questions: Are there really alligators in the New York sewers? Is London really awash with bottles of discarded Uber piss? (Yes, really.) What's the world's smallest skyscraper? And, most importantly of all: what's Barbara's favourite map? Oh, and in case you were wondering: no, this isn't the last episode (you don't get off that easily). Nor am I going to have one of those inevitably disappointing solo careers. From the next episode, Skylines will be co-hosted by the entirely excellent Stephanie Boland. Skylines is the podcast from CityMetric, the New Statesman cities site. It's presented by Jonn Elledge and Barbara Speed, and is a Roifield Brown production.