Heiwajima Onsen

Natural Hot Spring Heiwajima (天然温泉平和島) is a massive hot spring facility in Ota City situated conveniently close to Haneda Airport. It is located within BIG FUN Heiwajima, a large-scale entertainment complex that houses discount stores like Don Quijote, a bowling alley, a cinema, and a game center. While the complex has a nostalgic, established feel, the onsen itself is one of the most practical and spacious facilities in Tokyo, offering a deep, saline-rich natural spring water that is prized for its heat-retention properties.

The bathing area features several different pools, including a high-concentration carbonated bath, jet baths, and a large cold water plunge pool. For those seeking heat therapy beyond the water, there is a dry sauna and a ganbanyoku (hot stone spa). The facility is split into distinct zones, allowing bathers to choose between a television-viewing bath area or a quieter, more contemplative space without distractions.

Heiwajima Onsen Interior — The main bathing area uses natural sodium-chloride spring water.

Heiwajima Onsen is renowned as a hub for travelers due to its proximity to the airport. The facility offers extensive relaxation areas, including a manga room, napping rooms, and a restaurant. Its primary appeal for international visitors is the Late-Night Stay Packages. For approximately ¥4,500 to ¥5,500, guests can utilize the relaxation rooms as a dormitory overnight. This price typically includes a shuttle bus directly to or from Haneda Airport terminals, making it a highly cost-effective alternative to a taxi or a short-stay hotel for those with early morning or late-night flights.

Relaxation Lounge Heiwajima — Chairs in the relaxation room fold back almost horizontally for overnight rest.

While the standard relaxation chairs fold nearly flat, guests can also opt for the Premium Lounge for an additional fee (approximately ¥1,500). This area features fully reclining, first-class style seats with restricted access to ensure a quieter environment. Blankets are provided free of charge at reception. Luggage can be stored at the front desk, and secure lockers are available for smaller valuables. Note that while there is a dedicated female-only section, the main relaxation areas are mixed-gender.

Late-Night and Airport Packages

Stay Course: Allows for a stay from evening until the following morning, typically including a breakfast voucher.
Flight Course: Designed for those departing early; includes a shuttle bus to Haneda Airport Terminal 3.
Welcome Course: Ideal for late-night arrivals at Haneda; includes a shuttle bus from the airport to the onsen and a 14-hour stay period.

Advance reservations are required for the Flight and Welcome courses and can be made via the official website. Access from central Tokyo is also straightforward via a 10-minute bus ride from Heiwajima Station on the Keikyu Line.