Geography Reference
In-Depth Information
Portolan charts were made by medieval European mariners who plotted coastlines along
constant compass bearings. Drawn here in red ink, when put on the chart these bearings are
known as rhumb lines. They are often shown radiating from compass roses or compass stars,
which represent the 32 directions of the mariner's compass. There are four compass roses on
this chart, along the top edge.
Only part of this chart appears to have survived. Complete portolans always extended to
the eastern end of the Black Sea, but this section covers just the western Black Sea and the
eastern Mediterranean. It is possible that the chart originally continued further westward, too,
perhaps to Gibraltar, or even into the Atlantic. Whatever its original size, this surviving por-
tion still shows a wide area, and compares quite well for accuracy with much later charts.
Between the east coast of Greece at the lower edge and the west coast of Turkey at the top
lie the shores of Bulgaria and Romania, the Crimea, and the islands of Crete and Cyprus. The
outline of the coasts was drawn in black ink, now faded to brown, while some islands in the
Aegean Sea are coloured red.
The chart has been dated tentatively to the early 14th century, on the evidence of the many
place names, in both red and black ink, although they are very hard to read. They all lie along
the coasts and not in the interior, which was a constant feature of sea charts through the cen-
turies. The place names are in Italian, with a particular spelling which may point to a Vene-
tian origin. At this time, Venice was a flourishing maritime republic, with trading connections
across Asia, including those forged by its famous citizen Marco Polo. It was also one of the
centres of portolan production; the functional style of its charts contrasted with those of the
more decorative Catalan school.
We can only guess which of these seas this chart sailed, and in which ports it found safe
harbour around seven centuries ago. Its original purpose was hidden, and only 60 years ago
did it emerge again, to take its place as probably the oldest map in the archives.
