São Miguel Island, Azores
|Atlantic Ocean||Atlantic Ocean||Atlantic Ocean|
|Atlantic Ocean||São Miguel Island||Formigas Islets|
|Atlantic Ocean||Santa Maria Island||Atlantic Ocean|
São Miguel is a graticule comprising the Green Island itself and a small piece of the island to its south, Santa Maria. A land geohash in this graticule is rare but not extraordinarily so -- approximately 7-8% of the time the geohash will fall upon São Miguel instead of the Atlantic Ocean.
Still, a water geohash is very likely, and perhaps easier to fulfill since water transportation is presumably common in the Azores.
 Graticule Maps
Today's Geohash (switch to satellite mode to be able to see anything)