I cycled the Americas, including the stretch Colombia - Venezuela - (piece of Brasil) - Guyana - Surinam - French Guyana, in 2010.
Colombia was great, Venezuela the dirtiest (what a trash heap) and most dangerous place we have ever seen (still were ok after 3 months there, but other friends not so). The best part is the South, the Gran Sabana is wonderful (with Angel Falls and Mt Roraima, a great Hike. Remember the movie 'UP'?
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The 3 Guyanas are all wonderful, the most underrated part of South America. Note that getting a visa for any of these is (was) difficult, depending on where you from and where you apply.
I loved Surinam the most, but as I speak Dutch, I might be prejudiced (though I speak English (Guyana) and some French (FG) and of course Spanish as well). Great food, warm people, wonderful Nature. But the Jungle in Guyana and even the not so safe capital and Indian influences were great as well. French Guyana is different, but very much worth a visit as well, from Leatherback Turtles on the beach to French Croissants and the space centre.
Note that in all 23 countries we cycled through from Alaska - Patagonia, we met 99% nice people that helped us out whenever and however they could, whether we requested assistance or not.
