Manaus is the Amazon’s largest city, an incongruous urban metropolis in the middle of the jungle and a major port for seafaring vessels that’s 1500km from the ocean. The Amazonian rainforest has a population density half that of Mongolia’s, but the journey there invariably begins in (or passes through) this gritty bustling city. Don’t be surprised if you feel a little out of whack.
Manaus is no architectural gem, but does have some genuinely rewarding sights, including a leafy zoo and a rewarding beach-and-museum combo. It’s a place to stock up on anything you forgot to pack, make reservations and begin your journey out into the jungle, or refill your tank with beer and internet after a week in the forest.
Another bit of advice: don't get stuck here! Manaus is best enjoyed as a starting point for your Amazon adventure, not the end of your road into the Amazon.