Ishigakiyama Ichiya Castle: Odawara's Legendary "One Night Castle" with Free Weekend Guides

The Legendary Site Where Toyotomi Hideyoshi Made a Castle Appear Overnight

Stone walls (ishigaki) over 400 years old still stand here, offering panoramic views of Sagami Bay and the Hakone mountains. Ishigakiyama Ichiya Castle is a historic stage born from Toyotomi Hideyoshi’s bold military strategy.

On weekends and holidays, the Umemaru-go (sightseeing bus) takes you from Odawara Station in just 15 minutes. You can also explore the castle ruins with a free guided tour.

Here is a guide to the history and highlights of Ichiya Castle, along with the best way to get there.

Ishigakiyama Castle (Ishigakiyama Ichiya Castle)

Ishigakiyama Castle, also known as Ishigakiyama Ichiya Castle, is located in Odawara City, Kanagawa Prefecture. It is said to have been built in a single night by Toyotomi Hideyoshi during the Siege of Odawara. In 1590, Hideyoshi constructed this castle on Mount Ishigaki and established his headquarters there while besieging Odawara Castle.

Toyotomi Hideyoshi’s Overnight Magic Trick

The story of building a castle in a single night was actually a clever trick devised by Hideyoshi. In reality, he mobilized approximately 40,000 workers and spent 80 days constructing the castle.

Hideyoshi secretly carried out construction deep within a forest on the mountaintop, hidden from view of Odawara Castle. Once the castle structures were completed, he had all the surrounding trees cut down at once. Suddenly, a castle appeared on the mountaintop for all to see.

Odawara Castle as seen from Ichiya Castle

Imagine waking up one morning to find a castle towering on a mountaintop where nothing had stood the day before. It is said that the Hojo clan soldiers were so shocked that they lost their will to fight.

The castle’s official name is Ishigakiyama Castle, but thanks to this legendary episode, it became widely known by its nickname “Ichiya Castle” (One Night Castle).

Spectacular Stone Walls Standing for Over 400 Years

One of the main highlights of Ichiya Castle is the stone walls (ishigaki) that remain intact from the original construction.

The stone walls of Ichiya Castle were built using a technique called nozurazumi (rough stone stacking), where natural stones are stacked without being cut or shaped.

Seeing them up close is truly awe-inspiring. Because the stones were used in their natural form without cutting, the sight of massive boulders layered upon one another is breathtaking.

Nozurazumi is the oldest method of building stone walls (ishigaki). It first appeared in the late Kamakura period and is believed to have been used extensively during the Sengoku (Warring States) period in the 16th century.

The stone walls of Ichiya Castle are said to have been built by the Ano-shu (stonemason guild from Omi), a group of expert stonemasons from Omi Province. More than 400 years later, their original stonework can still be seen today.

From massive boulders to smaller rocks, everything remains in perfect balance. It is extremely rare for stone walls of this scale to survive in such condition.

While neatly cut and aligned stone walls have their own beauty, the rugged yet precisely stacked nozurazumi walls possess a powerful and compelling charm all their own.

Breathtaking Views of Mount Komagatake and Odawara Cityscape

Ichiya Castle sits atop Mount Ishigaki at an elevation of 262 meters. The views from here are wonderfully open and spectacular.

To the west, a sweeping landscape extends toward Mount Komagatake.

To the east, you can take in views of Sagami Bay and overlook the Odawara cityscape.

Even without climbing a mountain, you can enjoy this level of openness and stunning scenery, which is something unique to Ichiya Castle.

A Spiritual Power Spot Born of Sorrow and Devotion: Lady Yodo’s Makeup Well

Lady Yodo’s Makeup Well is located in the area known as Ido Kuruwa (the well bailey). The Ido Kuruwa is one of the sections of Ishigakiyama Ichiya Castle that has relatively preserved its original appearance, and the well is one such feature. It is popular as a spiritual power spot.

The well is approximately 2 meters in diameter and about 10 meters deep. Stone walls (ishigaki) were built around the well to protect its water supply.

The well gets its name from the legend that Lady Yodo (Yodogimi) used its water for applying her makeup.

The Battle of Odawara dragged on for approximately three months. Concerned about the hardships faced by the gathered feudal lords during the prolonged campaign, Toyotomi Hideyoshi summoned their wives to Ishigakiyama Ichiya Castle. Hideyoshi himself also summoned Lady Yodo.

Another theory suggests that Hideyoshi brought Lady Yodo to Ishigakiyama Ichiya Castle specifically to pressure the Hojo clan in Odawara Castle into surrender.

Lady Yodo: A Life of Turbulence and Tragedy

Lady Yodo (Yodogimi) was a consort of Toyotomi Hideyoshi and the birth mother of his heir, Toyotomi Hideyori. Her birth name was Azai Chacha. She was born as the eldest daughter of Azai Nagamasa and Oichi no Kata, who was the sister of Oda Nobunaga.

However, her life was marked by tragedy. Her father, Azai Nagamasa, took his own life at the Battle of Odani Castle in 1573. Her mother, Oichi no Kata, also perished alongside Shibata Katsuie at the Battle of Kitanosho Castle in 1583. Having lost both parents at a young age, Lady Yodo later became a consort of Toyotomi Hideyoshi and bore his heir, Hideyori.

Then came the Summer Siege of Osaka in 1615. When the Toyotomi clan met its end, Lady Yodo took her own life alongside her son Hideyori.

Fresh spring water still flows from the Makeup Well to this day, preserving the legend that Lady Yodo used this well for her daily grooming.

Having lost both parents as a child, surviving a tumultuous era as the consort of Japan’s supreme ruler, and ultimately perishing alongside her own son, Lady Yodo’s life story gives the spiritual power attributed to this well a weight that transcends the simple label of “power spot.”

Treat Yourself to World-Class Sweets: Ichiyajo Yoroizuka Farm

Right next to Ichiya Castle stands Ichiyajo Yoroizuka Farm, a shop run by Toshihiko Yoroizuka, one of Japan’s most acclaimed patissiers known worldwide.

Inside the shop, you will find locally grown vegetables, flowers, and fruits from Odawara’s natural bounty, as well as freshly baked bread and an array of sweets.

You can enjoy your purchases at the outdoor terrace seating, so after exploring Ichiya Castle, treating yourself to exquisite sweets is the perfect way to recharge.

Business hours are 10:00 to 17:00, and the shop is closed on Tuesdays and Wednesdays. The restaurant lunch service is by reservation only, so be sure to book in advance.

How to Get to Ishigakiyama Ichiya Castle

There are three ways to access Ichiya Castle:

1. By car
2. On foot from Hayakawa Station
3. By the Umemaru-go sightseeing bus, which runs from Odawara Station and Hayakawa Station on weekends and holidays only

1. By Car

If you have your own car or a rental car, you can drive directly to Ichiya Castle, where free parking is available.

2. On Foot from Hayakawa Station

From Hayakawa Station on the Tokaido Main Line, it takes approximately 1 hour to walk to Ichiya Castle.

However, this route involves a long stretch of steep uphill climbing, so it is not recommended.

3. By the Umemaru-go Sightseeing Bus

This sightseeing bus is the most recommended way to access the castle.

In Odawara, the Umemaru-go sightseeing bus operates on weekends and holidays only.

You can board the bus at Bus Stop No. 1 at Odawara Station East Exit. A one-day unlimited ride pass costs ¥600 for adults and ¥300 for children, allowing you to hop on and off at any stop as many times as you like.

Odawara Sightseeing Bus Umemaru-go - Odawara City

The ride from Odawara Station to Ichiya Castle takes just 15 minutes.

Weekends and Holidays Only: Free Guided Tours of Ichiya Castle

On weekends and holidays, volunteer guides from the Odawara Guide Association offer free tours of Ichiya Castle.

Tours are timed to coincide with the arrival of the Umemaru-go sightseeing bus. Groups of about 4 to 5 people explore the castle ruins together with a guide. (Even if you come alone, you will join other visitors.)

With a guide leading the way, you can learn about the history of Ichiya Castle while exploring, and you will not miss any of the highlights. Highly recommended.

The guided tours are available on weekends and holidays only, and best of all, they are completely free.

Since the Umemaru-go also runs only on weekends and holidays, you can see just how much value you get by visiting Odawara on a weekend or holiday and taking the sightseeing bus.

A Place to Savor History, Stunning Views, and World-Class Sweets

Ishigakiyama Ichiya Castle is a place of great historical significance, built by Toyotomi Hideyoshi, who also stayed here himself.

Today it serves as a public park with well-maintained walking paths. The grounds are not overly large, so walking around is comfortable. A typical visit takes about 1 to 1.5 hours.

There are many more things to see, including the open grounds where tens of thousands of soldiers once waited, and the rocks that were deliberately toppled when the castle’s role came to an end.

The open grounds where tens of thousands of soldiers once waited

Rocks deliberately toppled when the castle’s role came to an end

With outstanding panoramic views and world-class sweets on top of all the history, you are guaranteed a complete and fulfilling experience.

Ishigakiyama Ichiya Castle was the first castle built entirely with stone walls (ishigaki) in the Kanto region. Due to its advanced stone wall construction techniques and impressive scale, it has been designated as one of the Continued Top 100 Castles of Japan.

Come visit Ichiya Castle to experience Japanese history, culture, and exquisite sweets all in one place.