BBC reporter Paulo Cabral is travelling along Brazil's Sao Francisco river, following in the footsteps of Victorian explorer Sir Richard Burton. Each week day Paulo will be posting a diary entry on the web, and responding to a selection of your e-mails.
26 June: Januaria to Itacarambi
Dirt tracks and pot holes dominated my journey today. But in the middle of all that, there is Itacarambi. Colourful and spotlessly clean, this perfect little town on the banks of the Sao Francisco made me think of scenery from a Hollywood movie.
"Nobody would throw rubbish on the streets because he'd immediately be shamed by others" said a man in his 70s, passing the time of day in the shade of a tree. You're never far from a rubbish bin in this place, thanks to an enlightened mayor who has promoted clean living with a vengeance.
Posters everywhere urge residents to keep Itacarambi tidy, and promote the health benefits of giving up smoking, playing more sport and even dental floss. You can't argue with the sentiment but something about the town's concerns about health and fitness struck me as just a bit obsessive.
Visitors are urged to floss their teeth in health conscious Itacarambi
All this cleanliness didn't last long, though. Just ahead, 200km of dusty dirt tracks awaited me en route to Bom Jesus da Lapa.
I have nothing in particular against dirt tracks. In fact, I quite like them because they tend to lead to unspoiled places.
But it was quite hard to keep this positive attitude when the sharp gravel slashed a tyre resulting in my second roadside wheel-change in two days.
I'm glad I didn't know then that I'd be repeating the experience 8 hours later in pitch darkness, when one of the hundreds of potholes I encountered bent another wheel, just 15km from my destination.
This stop, however, gave me the chance to have a look at the sky: with no lights, no pollution and no clouds it's just amazing the number of stars you can see. There, I understood immediately where the Milky Way got its name from.
It's a perfect place for satellite spotting, a sport much appreciated by my producer Tracey Logan, who'se been an indispensible companion on the trip.
The environmental problems affecting the Sao Francisco River here are not so much local issues - the green water is very clean and the surrounding forests reasonably preserved - but caused by dams for hydroelectric power along its course.
The perfect place for a swim
"The dams hold back the water so that the river current can't carry away sand and gravel. The river is getting shallower", I learned from a 60 year-old farm worker with the knowledge and authority of someone who's lived all his life on these banks.
Thanks to the messages I've received from people following these blogs, I've learned that the problems faced by the Sao Francico River are echoed in other parts of the world. The Argentinean Maya Iriondo tells me that similar problems.
"The may-have-beens of a beautiful region", as she put it - exists in the Parana River, which marks the Brazil-Argentina border.
Carlos Ryes, from the Philippines regrets that his country's Panama Bay (Panama meaning plenty of fish in his native language) is so polluted it should now be called Sewage Bay. I'm happy to report back that the Sao Francisco river is nowhere near that bad yet.
That's thanks, in part, to the increased interest in its condition shown by recent Brazilian governments and environmentalists over the past few years, offering real hope that Old Chico - as the river is affectionately known - will be preserved for future generations.
25 June: Pirapora Rapids to Januaria
Captain Richard Burton, in September 1867 observed: "Hospitality is the greatest delay in Brazilian travel. You may do what you like. You may stay for a month, but not for only a day."
Crossing the bridge over the Pirapora rapids was scary but trouble free. Travelling on the road from Pirapora to Januaria should have been smooth, but it wasn't. For about 50km I managed to avoid the frequent and huge pot holes in the road, until one hidden beyond a bend resulted in a damaged wheel and an annoying delay.
But the hospitality in this region that Burton commented on turned that unfortunate accident in a great opportunity. I stopped at a garage to get the wheel hub bent back into shape and after the job was done the mechanic Adilson invited me to see the remains of an ancient church on the river bank.
Local people do not seem too concerned about preserving historic buildings
"I will take you there. You can't miss it", he insisted proud of the ruins set in his little home town of Barra do Guaicui.
Adilson was right. The roof of the church is long gone, but its stone walls and marble columns remain, topped by a giant gamaleira tree whose roots cling to both sides of one of the church walls. All this, little more than 20 metres from the waters of the Sao Francisco.
It is a site of great beauty, and yet it was hard to ignore that plague of our times - graffiti - left all over the church walls and even the giant tree roots by visiting tourists.
Driving on I completed the 350km journey to Januaria by early afternoon (Burton took four days), by which time the temperature was 30 degrees.
A perfect day to go to the beach and, despite being some 700km away from the ocean, I found one in Januaria on the sandy banks of the Sao Francisco.
Thanks to a public holiday I met many of the locals there, listening to Brazilian forro music and - of course - playing beach football.
Beach football: A way of life for many young Brazilians
Unfortunately, again the carelessness of some people is starting to mar the natural beauty of this place.
The water is clean and the surrounding landscape is thriving but on the beach I couldn't help noticing a few discarded cans, bottles and plastic bags threatening to spoil the view.
Rubbish bins along the sand would help to keep the area clean, but it would help even more if people that use the beach behaved more responsibly.
My next stop is the town of Bom Jesus da Lapa, home to a commune founded, originally, by escaped slaves. Despite a government decree granting them rights to the land they've been living on for two hundred years, local farmers are resisting their claim and threatening their heritage.
Finally, I have already started to receive e-mails about this journey with ideas of places to visit in the days ahead. Thanks for these - I'm already planning to include some of these detours in my route and will let you know how I get on.