Fort Santo Angel
Fort Santo Angel was a Spanish fortress on the island of Guam, now a United States territory.  Located on a promontory on the west coast of the island in the northernmost part the Umatac Bay in Umatac, the fort's remains are among the oldest known Spanish-era structures on the island;  a fort is documented to have been standing here since 1742, and to still be in use in the early 19th century.  The fort provided protection for the anchorage used by Spanish galleons on the trade route between Manila (then in the Spanish East Indies) and Acapulco, Mexico (then part of New Spain).  Perched on a monolith, there remains a plaza  of flagstone surrounded by a manposteria (coral mixed with cement) wall  high and  thick.  The remains of a guardroom and a second, smaller platform, lie to its west.

See also
National Register of Historic Places listings in Guam

References

Buildings and structures on the National Register of Historic Places in Guam
Forts on the National Register of Historic Places
Fortifications of the Spanish East Indies
Umatac, Guam