Miss USA Nia Sanchez -- Learns Name of Nevada Capital … Even Finds It On a Map

Miss USA Nia Sanchez ... who famously couldn't name the capital city of Nevada -- even though she competed as Miss Nevada -- paid her first official visit Wednesday to, um, that place.

The brunette beauty traveled to Carson City to meet with Mayor Bob Crowell … who diplomatically neglected to mention Nia's faux pas.

Sanchez caught some heat for competing in Miss NV, even though she grew up in Cali -- classic carpetbaggery -- and she only made matters worse when she wasn't able to name Nevada's capital.

Sources close to Nia tell us … she purposely made Carson City her first stop on her Nevada apology homecoming tour … since winning the Miss USA crown last month.