FUCK this was supposed to be posted eight hours ago, but since I'm done I'm doing this.
Manaus happens to be in the very middle of the Amazon Forest. I won't speak for them, but it's not the most accessible of locations and, despite the deforestation going on, it's still very much a 'tropical paradise' - insects, trees, few roads that are of good quality [due to the rains and all].
I'm sure things are 'better' nowadays, and it does have a 'Zona Franca' where commerce is good, but every other region is more accessible to a degree.
And speaking of regions... Brasil is separated in five different 'regions', based on their location, weather and economic position, which allow us to gauge just how unbalanced things are. We have the North, where Manaus is, best-known for the Amazon forest, being right close to Colombia and Venezuela, being the largest area in mass, and being harder to bring progress to because of all the trees. The Northeast is where the 'good beaches' are, the point where Cabral hit land [and thought this was an island, much like how Columbus thought the Caribbean was India], and a near desert due to deforestation and all. It's also the 'stereotypical' source of our immigration problem, sadly. The French and Dutch tried to colonize this area, not wholly successfully, before Portugal finally decided to give a crap.
The Southeast [which is in the middle of the nation] is where the money is most concentrated. That's the Rio-São Paulo-Minas axis, which includes our previous capital and the sources of our presidents during the Old Republic [yes we had one of those], as well as most of the gold we don't have anymore. It's probably the most developed area in the nation because it has all of the money. The South is very close to Argentina and Uruguay, nearly seceded once [as far as making itself relevant]. And finally, there's the Middle-West, which is close to Paraguay, has the Pantanal [a big-ass swamp that doesn't smell nearly as bad as you'd think], the current capital, and is the second-closest thing we have to the pits or where Judas lost his boots or whatever you call it. Surprisingly developed, but still very much lame.
The aforementioned capitals, Florianópolis [Floriano City] and Porto Alegre [Happy Port], are in the South. There's also Curitiba, which is a poor man's São Paulo.