The Malabar (southwest) and Coromandel (southeast) coasts, with their network of small trading ports, 1749

Source: ebay, Nov. 2004

"Thomas Jeffreys was an English engraver, geographer & publisher whose work was both prolific and of a high standard. This attractive map comes from the series he engraved for Salmon's "Geographical Grammar", first published in 1749, and is from the 1764 edition."

Source: ebay, Feb. 2005

For sailing ships, there were special coastal navigational charts

Source: ebay, Nov. 2004

"The Coast of India between Calymere and Gordeware Points including the Coast of Coromandel, by Laurie & Whittle,1794. This is a finely engraved map showing detailed depth soundings along the coastline. Early hand colour. (Ref Tooley M&B)."

Even on this very early map (1558), the density of known coastal towns is remarkable

Source: http://www.imagesonline.bl.uk/britishlibrary/controller/textsearch?text=india&idx=1&start=175
(downloaded Jan. 2005)

"Countries around Indian Ocean. Description:  (Double opening) Map of the Indian Ocean showing parts of Arabia, East Africa, Persia, Western India and Madagascar; in Ethiopia, Prester John is depicted on his throne. Title of Work:  Queen Mary atlas. Author:  Homem, Diego. Production: 1558."

The Americas too were explored in this way, with great coastal knowledge but little information about the interior (from a map by Matthaus Merian, Frankfurt, 1646)

Source: ebay, Nov. 2007

Venturing inland was a very uncertain enterprise, and towns were often depicted strung into long lines like subway routes (a map by Pierre du Val, 1666)

Source: ebay, Mar. 2004