Explore Hidden Treasures at the Unwanted Treasure Museum in Harajuku

Discovering Hidden Treasures at the Unwanted Treasure Museum

Overview of the Event

From December 4 to December 14, 2025, Mercari has organized an interactive exhibition named the "Unwanted Treasure Museum" at GoOn TOKYO in Harajuku. This museum is designed to highlight the hidden values of various household items that often get ignored during the year-end cleaning period. Within the first four days of its opening, the museum has already attracted over 1,000 visitors, thanks to media coverage and social media buzz, prompting the organizers to expand pre-reservation slots to accommodate the growing interest.

Experience of the Museum

At the museum, visitors have the opportunity to explore a nostalgic environment reminiscent of the 2000s, featuring the rooms of a young girl named Ayaka and her older brother Takeru, alongside a familiar family living room from the Heisei era. Over 1,500 items are on display, including retro gadgets, books and magazines that have not been read in years, and beloved character merchandise and toys. While these items might initially appear outdated or like junk, they hold actual value on Mercari, where many are traded.

The interactive setup encourages visitors to engage in nostalgic conversations, reminiscing about the good old days with comments like 'I used to have this!' or 'Which one was the most nostalgic?' Many attendees discovered that items they once owned were valued highly in the market, prompting remarks like 'I should never have thrown it away.'

Insights and Motivation Behind the Exhibition

According to a survey conducted by Mercari in November 2025, households in Japan hold an average of approximately 715,000 yen worth of unused items, highlighting a stark disparity between perceived and actual value. It was revealed that if sold, these goods could fetch an estimated price of about 195,000 yen, leaving a substantial gap of around 520,000 yen. This alarming statistic influenced the decision to create the Unwanted Treasure Museum, aiming to encourage people to reconsider the worth of items often deemed as trash before the year’s end cleaning.

Media Preview and Insights

Before its public opening, a press conference marked the event's launch, where the project lead, Saki Ikeda, from Mercari's Marketing Department, shared insights into the purpose behind the exhibition. The analysis indicated that nearly 90% of those who disposed of unused items last year felt that selling them would yield minimal profits.

With projections estimating that about 10 trillion yen worth of unwanted items are expected to be discarded nationwide this year—a staggering 89,000 yen per person—Mercari aims to educate the public about the unrecognized value in these items before they meet their demise in the trash bin.

The museum features three themed rooms where visitors can guess the prices of potentially valuable items listed on Mercari. Many items have seen a resurgence in value due to trends like the current retro boom, and through this exhibition, Mercari hopes to inspire visitors to reassess the potential worth of items they own.

Visitor Engagement

Since its opening, the museum has seen a vibrant influx of guests, buzzing with excitement over the exhibits. A spotlight section displays common household items that individuals might overlook during cleaning activities, showcasing their potential worth estimated at approximately 89,000 yen each. In addition, interactive features like a trash bin that transforms into a treasure chest at the press of a button add a layer of fun, accompanied by motivational quotes related to unexpected assets that dangle from the ceiling, enhancing the overall experience.

As guests traverse further into the main hall, they are met with four engaging missions. Participants predict prices using the market search function based on multiple-choice hints. The experience is enriched by surprises, with some discovering items unexpectedly of high value.

Capturing the Nostalgic Essence

Many visitors expressed feelings of nostalgia, particularly for items like old phones and stuffed animals. Their feedback, such as 'It made me reconsider throwing things away!' and 'I feel I’ve been wasteful by discarding everything,' suggests that the exhibition is successfully prompting reflections about their belongings as they prepare for the upcoming year-end cleanup.

The museum offers a unique exploration into the world of hidden treasures that often lay forgotten in homes. Through these enlightening experiences, attendees can discover the hidden gems among their possessions and perhaps reframe what it means to let go or to sell.

Event Details

- Exhibition Name: Unwanted Treasure Museum
- Dates: December 4 to December 14, 2025
- Hours: 12:00 PM - 8:00 PM (with special hours on the first and last day)
- Location: GoOn TOKYO, 6-33-14 Jingumae, Shibuya, Tokyo, 150-0001
- Access: 6-minute walk from Harajuku Station, convenient access from several subway lines
- Admission: Free, with reservation options available for priority entry.

Explore underappreciated items at the Unwanted Treasure Museum, and take part in this interactive journey reflecting the themes of value, nostalgia, and unexpected discoveries!