Built in 1871, this two-story structure on the corner of Bethel and Merchant was nominated as a national landmark exactly 100 years later,
as it is the first use of precast concrete block and steel reinforcement construction in the United States.
In 1987, it also became an American Society of Civil Engineers National Historic Civil Engineering Landmark.

It cost only $13,000 to build. Kamehameha V hired designer and builder J.G. Osbourne, known as an experienced brickmaker.

Osbourne designed the building based on memories of similar structures in his native Yorkshire, England.

It operated as a post office until 1992, suffering a number of bricked enclosures of the balconies and windows.
It reportedly at one time had separate windows for ladies, foreigners, Hawaiians, Japanese, Portuguese, and stamps.

Honolulu Star Bulletin