A morro is a promontory overlooking a harbor or a hill with good prospects for armed vigilance. Fortiﬁed heights in the Spanish Americas often contain morro in their name. Morro is sometimes confused with moro. A morro is a sentry hill, while moro is both the name of the North African Islamic culture driven from Spain by 1492 and a color that ranges from dark brown to near black. Still, a morro may be a hill as round as a turban and dark as Othello. El Morro, on the trail to the Zuni Pueblo, is the towering “Inscription Rock” on which the Spanish reconquest of New Mexico in 1692 was recorded, along with a thousand other travelers’ grafﬁti before and since. Morro Rock in Morro Bay in central California is one of a line of exposed volcanic plugs called the Nine Morros, named in 1542 by the explorer Juan Rodríguez Cabrillo.
At the end of the second day they made camp under one of these island promontories, pearly white like a bleached shell, around whose castellated top they heard great eagles mewing. Because of its inaccessible towered front, the Spanish-speaking called it El Morrow [sic], but now it is recorded as a national monument under a name coming naturally to the ﬁrst American discoverer of it: Inscription Rock.
— Mary Austen, The Land of Journey's End