Truly, Manaus is other-worldly.  I visited for a glorious week a number of years ago.  It is the safest large city in Brazil to carry around an expensive digital camera: as no roads connect Manaus to anywhere, and the jungle is forbidding, the only escape for criminals is by boat from its few ports.  The city itself was built over a century ago on the riches of the natural rubber boom. Besides meriting its own opera house (see Werner Herzog’s “Fitzcarraldo” for an idea of the challenges), Manaus was the second city in Brazil to get electricity (after Rio) and for a time the rich sent their shirts to be laundered in London.  Despite being 1,400km from the sea, Manaus has a deep-sea port, being only 40-80 meters above sea level.  There is no other place on earth like it.  The most remote, and unconnected, of backroads.  [please hover over images for captions]