関屋大橋, Transportation bridge in Niigata, Japan

Sekiya Bridge is a road bridge on Niigata Prefectural Route 16, crossing the Sekiya floodway near the point where the Shinano River splits. It is 278.7 m long and 17.3 m wide, with four lanes and sidewalks at both ends; the upstream sidewalk was originally the bridge of the Niigata Kotsu tram line, converted in 2003 after the line closed in 1999.

Completed on 20 May 1971 as a road bridge of National Route 8, it was built as the Sekiya flood channel was excavated near the point where the channel leaves the Shinano River. When the Niigata Bypass opened in 1974 and Route 116 was rerouted over Ariake Bridge, the crossing was reclassified as a prefectural road; in 1985 it became part of the Niigata-Kameda-Uchino line, now Route 16.

On the day of the Niigata Festival fireworks, many residents, mainly from the Aoyama district, gather on the bridge because the fireworks can be watched from a distance. The bridge carries Niigata Prefectural Route 16, the Niigata-Kameda-Uchino line, across the Sekiya diversion channel.

The bridge carries four lanes of Niigata Prefectural Route 16, with sidewalks on both sides; the upstream walkway was refitted in 2003 from the former Niigata Kotsu tram bridge. From 7:30 to 9:00 on weekdays a reversible lane gives three lanes toward City Hall, the left one reserved for buses. At the west end, the Aoyama-doshita intersection links Route 42 toward the Niigata Bypass and Kurozaki IC.

The bridge's upstream walkway was originally a bridge of the Niigata Kotsu tram line, which closed in April 1999; it was converted into a pedestrian path in 2003. The downstream walkway existed from the start, so the two sides have different origins.