The arched bridge highlighted in the accompanying wood-cut print is Senju Ohashi on the northern perimeter of Edo City. Built in 1594 at the head of the Sumida River, close to its junction with the Ara River, Senju Ohashi was the only bridge Shogun Ieyasu allowed to be built across a major river around his city. Its name comes from the poststation town of Senju on the Oshu-kaido highway to northern Japan.
The neighborhoods surrounding the bridge thrived as distribution centers of heavy commodities shipped from provinces for consumption in the city. What look like bundles of needles on the riverbank to the right of the print are stacks of lumber transported from the Ara's mountainous upper reaches. The timber was traded locally or forwarded to the main market downstream at Fukagawa.
Travelers, both on foot or horseback, were happy to have a permanent bridge in order to facilitate an easier entry into and departure from Edo rather than relying on the ferries or makeshift pontoons. This was a great advantage compared, for instance, with the ferry service crossing the Tama River on the city's southern boundary (See this column, Dec. 5, 2003).