The Modern Athens, i.e. Edinburgh. Willis says that its singular resemblance to Athens, approached from the Piræus, is very striking.
“An imitation Acropolis is commenced on the Calton Hill, and has the effect of the Parthenon. Hymettus is rather more lofty than the Pentland hills, and Pentelicus is farther off and grander than Arthur's Seat; but the old Castle of Edinburgh is a noble feature, superbly magnificent.” —Pencillings.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Athens from Infoplease: