Toi Kinzan | An Old Gold Mine in Izu — and Why Taiwan's Gold Museum Lost by 30 kg

The Taiwan Gold Museum mindset

Before visiting Toi Kinzan, there was a thought running in the background: Taiwan has its own gold museum in Jinguashi, near Jiufen, with a 220.3 kg gold bar on display. Then at Toi Kinzan, the wall reads: ギネスブック認定 (Guinness certified), 250 kg. Nearly 30 kg heavier.

A quiet moment of regret on Taiwan's behalf — followed immediately by the realization that these two places aren't really in the same category. Different scale, different history entirely.

The mine tunnel

The main draw at Toi Kinzan is walking the actual mine tunnel — about 100 meters of carved rock, arched ceiling, wooden support beams along both walls. The first thing you notice going in is the cold: mine tunnels run noticeably cooler than outside air, regardless of season. Bring a layer.

Deeper in the tunnel is a small shrine — 大山祇廠 (Oyamatsumi-sha) — where miners once prayed to the mountain deity. Seeing it lit inside a carved rock tunnel is unexpectedly quiet. The working lives of the people here were more complicated than most visitors think about.

The Keichō koban — chest by chest

In the exhibit hall, a display shows reproductions of Keichō koban gold coins: six black iron chests stacked together, each with small windows revealing a neat row of oval gold coins. The placard: minted 1601–1695, total production 14,727,055 ryō.

The number is hard to picture. But looking at the chests, it's difficult not to start thinking about where you'd store them. Anywhere, really. Anywhere at all.

Coin boxes and treasure chests

A nearby case holds a ぜに箱 (coin box) — an Edo-period household safe for everyday merchants — alongside a 千兩箱 (1,000-ryō chest). Both are wood-and-iron construction, plain but solidly made. Inside: reproduction koban, arranged neatly. The display conveys something about what money felt like as a physical object in that era.

The 250 kg gold bar

In the main exhibition hall, a glass case holds the gold bar that left Taiwan 30 kg behind. The label is clear: Guinness certified, world's largest display gold bar, 250 kg, purity 99.99%. The outer glass adds: 防犯ビデオ作動中 — security camera in operation.

You can touch it. Staff are present and will let you feel the gold bar — that's part of the experience.

The Story of This Place

This mine's story runs deeper than the cool air inside its shafts. Gold was first found here in 1577 (Tenshō 5), at first just panned as placer gold from the riverbed. During the Warring States period this was the domain of the Later Hōjō clan, and the gold pulled from Toi once served as vital war funds for Odawara Castle. When Izu later passed to the Tokugawa, the Edo shogunate treated the Izu mines as an important source of revenue—and in 1606 (Keichō 11) it brought in Ōkubo Nagayasu, the mining magistrate who had proven himself at the Sado gold mine, to oversee the site. He introduced new excavation and \"mizunuki\" drainage techniques, output soared, and the mining town grew so prosperous, house upon house, that it earned the name \"Toi Senken\"—Toi of a Thousand Homes. Some of the ōban and koban coins circulating in that era were struck from Toi gold, helping to underwrite the finances of the Tokugawa house. Total output is estimated at roughly 40 tonnes of gold and 400 tonnes of silver, second only to Sado in the Edo period, with tunnels running some 100 kilometres in total length and reaching as deep as 180 metres below sea level, until the mine finally closed in 1965 (Shōwa 40) and was reborn as the sightseeing site you can visit today.

What's charming is that this gold mine also \"welled up\" a hot spring. As the story goes, during the mine's development in 1611 (Keichō 16), hot water gushed from a shaft mouth (mabu = mine tunnel) within the grounds of Anraku-ji temple, becoming the origin of Toi Onsen—which is why it's also called the \"Mine's Bath\" or the \"Gold-Dust Bath.\" Legend has it that a monk named Rinsen cured his illness bathing here, so the spring came to be known as the \"Iō-sen,\" the healing waters prayed to for good health. As for the name \"Mabu-yu\" itself, one account traces it to the tunnel word \"mabu,\" while another says it comes from the name of the mine's discoverer, Mabu Hikohei—and both versions survive side by side to this day, neither having eclipsed the other. Deep inside the shaft stands a mountain-god shrine as well; it's said the miners would come to pay respects to its guardian deity, Ōyamatsumi-no-mikoto, before and after entering, praying for safety and for the gold veins to keep running. That old faith in the mountain god lives on now as a \"gold-luck\" power spot.

Standing there, listening to the echo of water dripping down the tunnel walls, you suddenly understand—what they dug out of this place wasn't only gold, but four centuries of a whole town's joys, sorrows, and prayers.

Before You Go

・Address: 2726 Toi, Izu City, Shizuoka
・Access: From Mishima Station (Shinkansen) → Tokai Bus to Toi approx. 70 min; or from Shuzenji Station → bus to Toi approx. 50 min; or ferry from Shimizu Port → Toi Port approx. 70 min
・Admission: Adults ¥1,200 / Children ¥600 (current fare under the new operator)
・Hours: 9:00–17:00 (last entry 16:30)
・For comparison: Taiwan Jinguashi Gold Museum gold bar is 220.3 kg; Toi Kinzan is 250 kg — a 29.7 kg difference
・For Izu travel options, check Klook or KKday