How many letters does the top answer for “the making of maps and charts” have?

The most common answer is cartography (11 letters).

Crossword clue: the making of maps and charts

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

cartography 11 letters wn-def

the making of maps and charts

mapmaking 9 letters wn-def

the making of maps and charts

of or relating to the making of maps or charts 75% similar → cartographic, cartographical