NYC's richest and most expensive ZIP code has an average income of $879,000 and a median sale price of $3.9 million. I spent an afternoon there — here's a closer look at the trendy area.

Tribeca, a trendy neighborhood in downtown Manhattan, is home to New York City's richest ZIP code, where the average income of residents is $879,000, Bloomberg reported. It's the fifth-richest ZIP code in the US, according to Bloomberg's ranking. Tribeca is "the epitome of downtown cool," according …