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BBC reporter Paulo Cabral has travelled along Brazil's Sao Francisco river, following in the footsteps of Victorian explorer Sir Richard Burton. Over the last two weeks Paulo has kept a diary on the web, and responded to a selection of your e-mails. This is his final entry.

4 July: Porto das Piranhas
On his trip from the Paulo Afonso Rapids to the Atlantic Ocean in November 1867, Richard Burton wrote: "My task was done. I won its reward, and the strength passed away from me. Two days of tedious, monotonous riding led to the Porto das Piranhas."

What a long way from Paulo Afonso to the Atlantic Ocean!

First, I had to relax by the green waters of Lake Xingo with a chilled glass of fresh Guava Juice. Then, a few kilometres later, I enjoyed the hospitality of the Brazilian Environmental Police - including a fresh, homemade lunch in their barracks.

Coconuts grow on sand dunes where the Sao Francisco meets the Atlantic

Oh, and there was that visit to the pretty town of Piranhas and a dip in the (thankfully Piranha-free) river there.

> At the coast next morning, I felt compelled to take a boat - hammock included - to visit the mouth of the Sao Francisco River, where its calm waters clash noisily with the Atlantic Ocean.

Then there was that gentle stroll among golden sand dunes in the shade of coconut trees. For Burton, this final leg of his journey was "tedious", but I didn't think it was all that bad.

In Burton's time tourism was not yet a major industry. People travelled because they had to, rather than for fun.

So, in seeking out potential sources of "wealth for the distressed classes of Europe", Burton's mind was more on minerals, crops, and transportation than the potential value of the Sao Francisco valley's beauty spots.

Wildlife police display the traps they have seized

For me it was even more pleasant, then, to stumble upon to find Picabucu, a small village by the Atlantic that I would strongly recommend to the stressed classes of 21st century Europe or, indeed, any other part of the world.

If not totally virgin, the final stretch of the Sao Francisco River can certainly be classified as very well conserved.

That doesn't mean problems don't exist, though. The trade in wild animals and the destruction of forests for charcoal production are among the most severe.

But on a positive note I met a few men from State of Alagoas' Environmental Police who showed huge enthusiasm and determination in their mission of fight crimes against nature.

Such a commitment is certainly necessary to cover the lack of manpower: they have only 200 agents covering a State approximately the size of Switzerland.

Sailing to the mouth of the river with some local guides

"It's a moving experience to release birds back into the wild that we've found captured by traders and sold in street markets," said Private Altair.

"When they escape their cages, the birds fly over our heads for a few moments and then swoop close to the ground to thank those of us who have released them. I have already seen policemen crying when they see this."

Hopefully such good vibes will prevail and this environment will be kept just the way it is. I have finally reached the mouth of the Sao Francisco River - one of a handful of places on our planet that I think everybody should see.

It's a point were one of the greatest rivers in the world meets the vast Atlantic Ocean. The forces release in this clash of the Titans is truly awe-inspiring and demands our full respect and admiration.

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