Located in Hitachinaka City, [Hiraiso (Hiraiso) Beach] is a rare beach in Japan that resembles a “natural pool with calm waves,” surrounded by sturdy seawalls. Thanks to its unique topography, it is known as an ideal summer spot for families with small children and international tourists who want to enjoy the sea in peace.
In this article, we’ll share the secrets behind “Daichan the Whale,” the symbol of Hiraiso, along with a forecast for the 2026 summer swimming season.
The Star of Hiraiso Beach | “Daichan the Whale” Floating in the Sea
What has made Hiraiso Beach famous overnight is the giant orange whale floating on the sea, commonly known as “Daichan the Whale.”
- Sea Slide: During the summer, Daichan plays a major role as a floating slide in the ocean. The exhilarating feeling of diving into the sea from its back creates unforgettable summer memories for children.
- Resting on the Sandy Beach: Actually, Da-chan only floats in the sea during the swimming season (mid-July to late August). During the off-season, he is pulled ashore and quietly “rests” on the sandy beach. Taking a photo with Da-chan on the beach is a privilege reserved for travelers visiting from fall through spring. You’ll encounter a somewhat endearing expression that’s quite different from his appearance when floating in the sea.
[Summer 2026] Hiraiso Beach Opening Schedule Forecast
Based on last year’s opening dates (July 19–August 24, 2025), we predict the 2026 swimming season schedule.
Predicted Swimming Season
Approx. July 18 (Sat), 2026 – Approx. August 23 (Sun), 2026
The beach is typically open from the third Saturday in July to the fourth Sunday in August. During this period, a parking lot with a capacity of approximately 100 vehicles will be available, and voice gate announcements in foreign languages are expected to be provided to support safe swimming.
Enjoying the unique charm of Hiraiso Beach with its calm waves
Due to its unique topography, Hiraiso Beach offers a calm environment unlike other open coastlines.
- A "natural pool" environment surrounded by breakwaters Its most distinctive feature is that it is protected by sturdy breakwaters, making it less susceptible to the open ocean and resulting in very few waves. Since the risk of being swept away by waves is relatively low, you can relax and enjoy the sea even when spending time at the water’s edge with small children.
- Rock Pool Exploration: Observe Marine Life Right next to the sandy beach lies a rocky shore (rock pool). In the tide pools that appear when the tide goes out, you can observe creatures such as crabs and small fish up close. Beyond just swimming, you can enjoy a valuable experience exploring the rock pools and learning about Japan’s rich natural environment.
Advice for International Visitors | How to Enjoy Hiraiso Beach Safely
Check out the local rules to make the most of the calm waters at Hiraiso.
- Lifeguards and Announcements: Lifeguards are stationed during the open season, and safety announcements are made in foreign languages.
- Health and Safety: Swimming after drinking alcohol is strictly prohibited. Also, be sure to stay hydrated and take breaks to prepare for Japan’s strong summer sun.
- Etiquette: Open fires (BBQs) and overnight stays on the beach are prohibited. Please take your trash home with you to preserve this beautiful natural environment for future generations.
Hiraiso Accommodations and Campgrounds Near the Beach
The Hiraiso and Ajigaura areas offer a variety of charming accommodations to suit your travel style.
- Nearby Accommodations: Right next to the beach, you’ll find “minshuku” (guesthouses) and “ryokan” (traditional inns) where you can savor fresh local seafood. Spending time in a tatami-mat room listening to the sound of the waves is a precious experience that lets you truly immerse yourself in Japanese culture.
- Camping & Glamping: If you venture a bit further toward the nearby Ajigaura area, you’ll find plenty of camping facilities where you can feel the sea breeze, such as “Iba-fornia Beach Camping Place.” We recommend combining swimming with outdoor activities.
A symbol of Hiraiso Beach, loved year-round
Whether swimming energetically in the sea during the summer or quietly waiting for summer on the sandy beach during the off-season, both scenes capture the charm of “Daichan the Whale.” Why not create a special memory at the Hiraiso beach—a place cherished by locals and offering a unique atmosphere distinct from flashy resort destinations?
Location Data: Hitachinaka City, IbarakiHiraiso Town
Access: From JR Joban Line “Katsuta Station,” transfer to the Minato Line and get off at “Hiraiso Station.”
By car, it’s about 10 minutes from the Hitachinaka Interchange on the Joban Expressway and the North Kanto Expressway.