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Nice work on Tarapoto! I wouldn't worry too much about the formatting, since that's something anyone can fix up later, whereas your personal knowledge of the place is something that basically no one else will be able to contribute. If you are looking for stylistic inspiration, though, a good place to check might be one of the Wikitravel:Star articles, which is the designation Wikitravel gives to its best and most complete articles. Since you are writing about an off-the-beaten-path, small city, Sheki and Ubud might be fun to take a look at.