I`m specialist in medieval portolan charts, a still unsolved mystery of science. I hope to find on Wikipedia people with similar interest or with usefule information.
After completion in 1/2013 this pages were deleted from Wikipedia. A discussion found them unsuitable. They are now on another Wikimedia system and still intended for collaborative improvement of knowledge. Any suggestions please on my User Talk Page. The pages were deleted again. If you consider to work on the topic, you may ask here or here for temporary access.
1. What is unsolved about portolans? The Problem of the Portolan Charts
2. With focus on cartometric: The History of Portolan Research
3. Some info on oldest chart: Carte Pisane
4. The portolans of the North and the relation to the southern portolans: "Caerte van Oostlant"
5. The most important portolan and the transmission map: Pizigani 1367 Chart
6. A crucial issue: The Ptolemy Problem
7. The root origin: Traces of a Classical Portolan World Map And how the survey was done and the role of the Secret Courts.