12219 ／ いちはらし
Chiba PrefectureA cliff keeps Earth's magnetic reversal.
Geomagnetic reversal strata01 ／ Provincial nunnery
Kazusa Kokubunniji Ato is the site of one of the state temples built across the country by decree of Emperor Shomu in 741. The nunnery's formal name was Hokke Metsuzai no Tera. A national historic site, it has its middle gate, an eight-legged gate, and part of its corridor reconstructed.
02 ／ Tumulus
Anesaki Futagozuka is a keyhole-shaped tomb 114 m long on a sand ridge. In 1945, while pine roots were being dug up, grave goods came to light. The stone pillow is black talc, with chokkomon patterns in three tiers on its side. The prefectural board of education calls it the finest stone pillow found in the prefecture.
03 ／ Natural monument
The ginkgo at Iigaoka Hachimangu, to the right of the main hall, a national Important Cultural Property, splits in two at about 2.8 m above ground. It is about 16 m tall with a trunk about 7.6 m around, and became a prefectural natural monument in 1935. The shrine tradition tells of its planting, but the prefectural board says its age cannot be fixed.
Now and 1974–78. Tap a photo to zoom in.
Wide (about 6 km across)
Close (about 1.5 km across)
Now (shot June 2024)Shot 1974–78
Source: Geospatial Information Authority of Japan (GSI) GSI Tiles（全国最新写真（シームレス）／国土画像情報（第一期：1974〜1978年撮影））
Living here
The city's gateway is Goi Station on the JR Uchibo Line. The fastest daily train is a rapid on the Keiyo and Uchibo Lines, 57 minutes from Tokyo (October 2026 timetable). City Hall is about 10 minutes by bus from the east exit of Goi Station.
−1.9% since 2015
277,061 → 269,524
229.94km² of it habitable
2024
2.3 people per household
2020
National average 60,630 yen
2023
6.4 per 10,000 people
2023
These 3 items are waiting on a nationwide data source. We do not fill them with estimates.
ACCESS
Travel times follow JR東日本の駅の時刻表（2610版）。五井駅の下り（内房線 木更津・館山方面）の平日ダイヤ・土曜・休日ダイヤの列車ページから、東京の発→五井の着を数えた（docs/handoff/tools/jr_count.py を毎日運転だけに絞って使い、特急と快速の全列車を目で確かめた） (checked 2026-10-22). They vary by time of day.
Shape
North to south
36.7km
If something caught your eye, ask the town itself.
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