Carnaval in Rio? Claro. But if Carnaval in Salvador is not on your bucket list, too, you need a bigger bucket. Rio de Janeiro is Brazil’s smiling face; Salvador da Bahia is its pulsing, proudly African heart. In Rio, Carnaval is mainly a spectacle, staged in a stadium called the Sambódromo, which feels like a cross between the Colosseum and Caesars Palace. In Salvador, the action is still in the streets. It’s centered on the blocos, lavishly painted and costumed troupes analogous to, but sometimes edgier than, the escolas de samba that compete in Rio’s parades. The blocos, in turn, are centered on the trios elétricos: musical juggernauts, akin to monstrous Mad Max rigs or siege engines from Mordor, but studded with speakers rather than guns or lances. The musicians—once an eponymous trio, now any configuration that fits—ride the open platforms, three stories high.

Rio de Janeiro is Brazil’s smiling face; Salvador da Bahia is its pulsing, proudly African heart.

To experience the trios, you have three options. You can wear a special T-shirt called an abadá and join the pack of dancers trailing one of the trucks, in which case you’ll be paying for the privilege of restricting your listening to a single band. You can pay to sit in a camarote, a box in a viewing stand, in which case you might as well be in Rio. Or you can, at no charge, join the pipoca, or “popcorn”—the throng on the street that bursts into jigging, shimmying Brownian motion as each successive band inches by. If, like me, you’re mildly phobic of both claustrum and agora, being packed into a mosh pit at the foot of a towering, migrating stage takes some getting used to. But the brazillions of human molecules will soon attune you to their own laid-back, fun-forward frequency.