How many letters does the top answer for “a paved surface having compressed layers of broken rocks held together with tar” have?

The most common answer is macadam (7 letters).

Crossword clue: a paved surface having compressed layers of broken rocks held together with tar

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

macadam 7 letters wn-def

a paved surface having compressed layers of broken rocks held together with tar

tarmac 6 letters wn-def

a paved surface having compressed layers of broken rocks held together with tar

tarmacadam 10 letters wn-def

a paved surface having compressed layers of broken rocks held together with tar