Perhaps Seattle, WA? The Seattle FM's do well because stations in the large neighbouring markets are spaced appropriately, but every frequency on the dial has something on it, and on many occasions, multiple stations.
Yup, all of those new FM signals. Some frequencies with two or more stations on it causing funky signal swapping while driving. 95.1 in my area has three stations that are fringe reception. If a frequency was clear a few years ago, it has a station on it now. It stinks that not everyone has HD Radio. It could clean up some signals.
It is enough to drive ANYBODY to satellite, especially when the formats on all these new translators and LP's SUCK. Where I live, it is the battle of the Spanish religious stations to get as many translators as possible. One bad ultra fringe signal with a ten mile radius after another. Ridiculous, especially when none of them will EVER show up in ratings.
I've been to NY, Chicago, and LA. The dial is packed, but strong locals - especially with HD - jam first adjacents so you actually can receive less stations than other areas. Central Florida is one place where you don't have too many strong locals, so first adjacents have a chance. Near Disney, I've been able to hear different stations on maybe 85 or 90 frequencies. Everything from Jacksonville to Miami, although some are extremely weak. Late night, after a day of thunderstorms, the band opens up with skip and you can get nearly 100% of the frequencies.