Tsukui Castle
A mountain castle on the slopes above Lake Tsukui in Sagamihara, Kanagawa, built by the Miura clan and later used by the Hojo. Its commanding hilltop position overlooking the modern reservoir creates a dramatic scenic contrast between the ruined stone walls and tranquil water below.
| Japanese Name | 津久井城 |
|---|---|
| Prefecture | Kanagawa Prefecture (神奈川県) |
| Region | Kanto (関東) |
| Castle Type | Mountain Castle |
| Year Built | 1537 |
| Designation | 続100名城 |
| Coordinates | 35.5833, 139.15 |
Tsukui Castle rises dramatically from the slopes above Lake Tsukui in Sagamihara, Kanagawa Prefecture, representing a mountain fortress built in 1537 by the Miura clan during a period of intense regional competition. This strategic stronghold later fell under the control of the Hojo clan, one of the most powerful daimyo families in the Kanto region.
The castle was constructed to defend against rival clans and control the surrounding territory during Japan's tumultuous Sengoku period. Its elevated mountain position provided exceptional surveillance capabilities and made it exceptionally difficult to assault. When the Hojo clan consolidated power in the region, they maintained and reinforced the castle's defensive systems, ensuring it remained a crucial component of their territorial defense network.
The site's most striking characteristic is the dramatic contrast between its ruined stone walls and the tranquil waters of the modern Lake Tsukui below. The reservoir, created in the 20th century, has transformed the landscape surrounding the castle while simultaneously highlighting its stark stone foundations against the contemporary landscape. The weathered stone structures testify to medieval construction techniques and the castle's strategic importance to regional powers.
Climbing to the hilltop ruins offers visitors both historical insight and panoramic views across the modern Sagamihara region. The preserved stone walls remain largely intact despite centuries of exposure, providing tangible evidence of the craftsmanship and durability of medieval Japanese fortifications.
Tsukui Castle is recognized as one of Japan's second 100 castles as designated by the Japan Castle Foundation, a distinction that highlights its historical and architectural importance among the hundreds of castle sites across the country. As a mountain castle, its design reflects the defensive priorities and construction techniques of its era, with origins dating to 1537. Visitors traveling to Kanagawa Prefecture can explore the site alongside other regional historical attractions.
On the Ground
| Address | Magino, Midori Ward, Sagamihara, Kanagawa Prefecture, 252-0187, Japan |
|---|---|
| Car parking | 4 car parks within 1.5 km — nearest about 98 m away |
| Public toilets | None recorded within 1.5 km |
Car parks and toilets are counted from OpenStreetMap within 1.5 km of the castle coordinates, as recorded on 2026-08-15. They are not necessarily run by the castle, and OpenStreetMap does not record every facility — “none recorded” does not mean there are none.
Castle Hopping from Here
| Castle | Distance |
|---|---|
| Hachioji Castle 八王子城 | 12.9 km |
| Takiyama Castle 滝山城 | 14.0 km |
Distances are straight-line between castle coordinates, not travel distance. Only castles within 30 km are listed.
Is It Original?
| Original keep still standing? | No — this castle is not among the twelve in Japan whose keep survives from the pre-modern period. Any tower here is a later reconstruction or the site is a ruin. |
|---|---|
| Classification on this site | Historic Ruins |
| Nationally designated properties recorded here | — (none found in the database) — please check with the castle directly |
The count of twelve surviving keeps is stated independently by the official sites of Matsue, Maruoka, Matsuyama and Bitchu Matsuyama (checked 2026-09-04). Each of the twelve carries its own source on its own page. The classification line below it is this site's own grouping, not an official designation. The designated properties below it come from the Agency for Cultural Affairs national database of designated cultural properties (国指定文化財等データベース), retrieved 2026-08-13. A missing line means no entry was found in that database — not that the property is undesignated.
Location
View larger map — © OpenStreetMap contributors
Sources and What a Blank Means
Data on this page comes from OpenStreetMap and the Agency for Cultural Affairs national database of designated cultural properties. Checked 2026-08-22.
A blank or missing line means we found no record in those sources — not that the castle lacks the thing. Admission fees, opening hours and access change without notice; please confirm with the official site before travelling.