JAPAN ALMANAC
Interpretive illustrated fallback for Oshi Castle; not a site photograph.

Castle Atlas / No. 118

Oshi Castle

Oshi Castle is Foundation list no. 118, recorded in 埼玉県行田市 as a 平城 site associated with 成田氏 and 成田氏、松平氏、阿部氏.

Open in Google MapsOfficial visitor source

History

What historically stood here

The Japan Castle Foundation records 忍城 as a 平城 site in 行田市, with the founding label 15世紀後半（文明11年（1479）以前）. The listed builder or associated clan is 成田氏; principal lords are 成田氏、松平氏、阿部氏.

Today

What you are actually seeing today

The atlas currently classifies the visible condition as research pending. Check the linked operator page for current hours, fees and restoration details.

Current condition
Rebuilt or replica keep
Terrain
Hirajiro: flatland castle
Condition note
Keep built after 1868: 3重3階／1988年再／RC造外観復興. Classified 2026-09-24 from the structured fields at https://cmeg.jp/w/castles/2065.

Architecture And Defense

How to read the place

This record still needs feature-level reporting. For now, do not assume the most visible modern structure is the most historically important part of the castle.

Cultural-property notes in the Foundation row: 県指定旧跡.

Visit

Present-day visitor information

Foundation-linked visitor source available; current hours, fees, closures and restoration information have not been republished in this first atlas pass.

Address or access location
埼玉県行田市本丸17-23
Coordinates
36.137772, 139.453984
Nearest useful station
See official visitor information.
Estimated visit duration
See official visitor information.
Opening hours
Check the official visitor source.
Admission
Check the official visitor source.

Nearby

Castles close enough to compare

Sources

Source and correction context

Identity, list membership, Foundation list number, municipality, basic classification and cultural-property notes are source-verified. Site-level visitor details require additional review unless this record is publishable. Foundation numbers are official list identifiers, not rankings. Coordinates use the Foundation-linked position-data KML and should be treated as visitor-planning coordinates rather than archaeological survey points.

Sources

  1. Continued Top 100 Japanese Castles, Japan Castle Foundation. Accessed 2026-09-04. Used for the official identity, list number, list membership, location municipality, castle type, founding label, builders, principal lords, and cultural-property notes for the continued 100-castle selection.
  2. Japan's Top 100 and Continued Top 100 Castle Position Data, Japan Castle Foundation / Nippon Castle. Accessed 2026-09-04. Used for the 200 castle addresses and coordinates exposed through the public map linked from the Japan Castle Foundation castle-search page.
  3. 100 Fine Castles of Japan and Continued 100 Fine Castles of Japan, Wikipedia contributors. Accessed 2026-09-04. Used only as a secondary cross-check for common English castle names; Japan Castle Foundation records remain the corpus source of truth.
  4. Nippon Shiro Meguri castle records: keep structure, remains and rebuilt structures, Nippon Shiro Meguri (cmeg.jp). Accessed 2026-09-24. Structured fields for each of the 200 castles, used to classify what stands at each site today. The linked record for each castle is its coordinate source.