Hakone Black Eggs: A Hot Springs Specialty

From unconventional ice cream flavors to canned bugs in vending machines, Japan is no stranger to bizarre and novel foods. Perhaps the most curious of them all is also rumored to add seven years to your life: the black eggs of Hakone.

Just a little over an hour away from Tokyo, Hakone is one of Japan’s most famous hot spring resorts. It is home to its own Hell Valley known as Owakudani, which is where the onsen resorts in the area source their spring water. Only available at Owakudani, the “kuro tamago” or black eggs are a major tourist attraction because according to the local lore, one egg will add seven years to your life. As the name suggests, the shells of these eggs are black. However, black eggs are actually regular chicken eggs that have been boiled in the natural onsen waters. The sulfur in the water turns the egg shells black, though the inside is just a normal hard-boiled egg that is perfectly safe to eat. Black eggs are sold all year round and can be bought in a pack of five for ¥500. For 35 extra years, that doesn’t sound too bad! Some customers report that the yolk of the egg had more umami flavor than regular hard-boiled eggs.

Visitors can also witness how these eggs are made by taking a ride up the mountain using the Owakudani ropeway station. Uncooked eggs are placed in a basket and set in an onsen pond called an “egg pond” for an hour at a temperature of 80°C (about 175°F). After their soak, the blackened eggs are then steamed for about 15 minutes at 100°C (212°F). Finally, the finished eggs are transported up the mountain via a designated ropeway.

The black egg was first conceived in 1955 (Showa 30) by Oku-Hakone Kanko Co., Ltd., which established it as a specialty of Hakone due to its unique cooking process. At that time, the eggs were considered a luxury omiyage, or souvenir, to bring home. When the Owakudani Ropeway opened in 1959, the eggs became more readily available and their popularity skyrocketed. It is unknown how many eggs are made and sold each day, but they are so popular that other types of black egg omiyage such as t-shirts and keychains are also manufactured and sold in the area.

About the author:

Samantha Kwok

Samantha is currently a 5th-year JET in Okinawa, originally from Hawaii. She has been somewhat connected to Japanese culture her whole life despite being Chinese American. She's had the privilege of traveling to Japan and experiencing Japanese culture at a young age. She loves food and is always looking to try new places. When she is not working or out eating, she is an avid baker at home and has been known to feed her colleagues an excessive amount of baked goods.