The Bosque is a private forest reserve owned by Steven and Aurea. It is located in the same region (about half hour drive south from the city centre) where Henry Wickham (who took the rubber seeds out of Brazil from this area) set up house.
The reserve is an arboretum, where the trees have been identified and good trails have been laid out. You always go with a guide. There is a little museum as well. If you have little time, but are interested in local flora or have lots of time, but want to know more about flora before you go into the rainforest, this is a great place to go. Also good for birdwatching.
At the moment the Bosque only works with groups. There is a very informative blog website, which will give you an good idea of what the place is like. Just google Bosque Santa Lucia, Santarem.
Steve has also written a nice guidebook and chronicle about Santarem, Riverboat Town. Get it from Amazon before you go.
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