Les Halles is very central, very historic and very energetic. It’s the neighborhood that almost never sleeps. Centuries ago, it was a sprawling food and wares market. Now it’s a sprawling underground shopping center surrounded by street performers (watch out for pickpockets), mainstream stores, an iconic cathedral (the wildly-underrated Saint Eustache), modern gardens and two fantastic art museums (Collection Pinault for contemporary art and, not too far east, the world-famous Centre Pompidou). And most importantly, beaucoup late-night dining…