Bounded roughly by Fort Street at the southeast end and Nuʻuanu Avenue at the northwest, its older, low-rise, brick and stone buildings, surrounded by contemporary, concrete high rises, serves as an open-air, human-scale architectural museum of the city's commercial development between the 1850s and the 1930s.

Its original coral stone walls are no longer visible under its layers of stucco and paint, and it now houses city government offices, not private businesses.

[2] The Kamehameha V Post Office at the corner of Merchant and Bethel Streets was the first building in Hawaiʻi to be constructed entirely of precast concrete blocks reinforced with iron bars.

Its distinctive features include a corner entrance, arched windows and doors, fine masonry work, and brick pilasters below an ornamental cornice and parapet along the roofline, all of which are obscured to some extent by its current exterior of monotone white stucco.

[5] The bare stone face of the tiny Bishop Estate Building at 71 Merchant Street is a fine example of the stolid Richardsonian Romanesque style that was popular when it was built in 1896.

Constructed of dark lava from the Estate's own quarries, its notable features include arches above the lower door and window frames, four rough stone pilasters on the upper level, and a corniced parapet along the roofline.

Built on land that used to house the medical offices of Dr. Gerrit P. Judd,[7] the new building served as the first headquarters of Alexander & Baldwin, and also of the Bank of Hawaii until 1927.

Its Italianate design includes a triumphal arch over the main door, copper window casings, glass wainscoting, marble trim, and paintings inside by a local artist.

[9] On the day that Pearl Harbor was bombed, the building was taken over by the Alien Property Custodian, the first floor became a warehouse for confiscated possessions, and extra showers, toilets, and holding cells were installed in the basement to accommodate up to 250 drunken military personnel.

Architect Louis Davis designed it in a Spanish Mission Revival style that matches very well that of the newly built city hall, Honolulu Hale (1929).