In the early decades of Japanese administration, Hamasen was the center of everything in Kaohsiung. The city's first modernized street was laid here. Tap water arrived here before it arrived anywhere else in the city. Electric lights illuminated Hamasen before they illuminated the neighborhoods to the north and east. Before Kaohsiung Station was built — before the city had the infrastructure that would eventually define it — Hamasen served as the regular stop for passenger trains. All of this happened in a district wedged between the foot of Ape Hill and the edge of Yancheng District, tucked into the southern reaches of Gushan District where the harbor bends. The geography forced the infrastructure: this was where land, rail, and water converged most naturally, so this is where the city's modern nervous system took its first shape.

Railway and ocean cargo defined Hamasen's working identity. The two rail lines for which the neighborhood is named connected it to the broader island infrastructure, while the harbor provided the connection outward to the world. Politics, economy, and the fishing industry all concentrated here during Hamasen's peak years. Fishing boats moved through the same waters as cargo vessels. The harbor wharf that served Hamasen still connects Gushan District to Cijin Island across the water, with the Cijin-Gushan Ferry running its regular route — a service that endures because the geography that made it necessary has not changed. The water is still there. The island is still there. The ferry still runs.

Hamasen's western edge is defined by Ape Hill, the rocky promontory that rises between the harbor district and Sizihwan Bay to the west. The hill that once formed a natural barrier now contains a pedestrian and cycling tunnel that punches through to National Sun Yat-sen University on the other side. The tunnel transformed what had been a geographic obstacle into a connection, linking the historic harbor district to the university campus and the open bay beyond it. It is a practical piece of infrastructure that also captures something about how Hamasen has changed: where the neighborhood once faced inward toward the rail lines and the harbor economy, it now faces both directions — toward the water on one side, toward the university and Sizihwan's beaches on the other.

Hamasen today occupies a curious position in Kaohsiung: old enough to carry genuine historical weight, connected enough to remain active. The Hamasen Station of the Kaohsiung MRT sits within the district, folding a neighborhood that predates the city's mass transit system into the rail network it effectively preceded by decades. Fishing boats and yachts still berth at the harbor wharf. The alleys and older buildings preserve traces of the Japanese-era street patterns that predate postwar development. Yancheng District, another historic quarter, borders Hamasen to the east; together they form a corridor of older Kaohsiung that survived the rapid development of the postwar decades without being entirely consumed by it. Hamasen arrived first, and in some essential way, it has refused to entirely leave.