Overview

Wake to broad views of the Pacific at Mikazuki Sea-Park Hotel Katsuura, a seaside resort where hot spring bathing, swimming, dining, and family entertainment come together under one roof. From your room, you can look towards Katsuura Port, the sandy shoreline, and the changing colours of the ocean.

The main attraction is the combination of a natural hot spring bath high above the coast and Aqua Palace, a large swimsuit spa with indoor and seasonal outdoor pools. You can begin your day with a view of the sea, spend the afternoon moving between warm pools and water jets, then enjoy a lively buffet filled with seafood and local dishes.

With Japanese rooms, large suites, bowling, karaoke, table tennis, a game centre, children’s areas, and nearby beaches, the hotel works especially well for a family holiday or a trip shared across several generations.

Accommodation

The main room categories face the Pacific, placing the sea at the centre of your stay. Depending on the building and floor, you can look towards Katsuura Port, the white beach, or the open water. Room choices include large VIP suites, Special Rooms, Japanese-Western rooms, and traditional Japanese rooms.

The two VIP Rooms provide more than 100 square metres of living space. One layout combines a 15-tatami Japanese room with a separate living room and connecting twin bedroom. The other has a 12.5-tatami Japanese room, living area, and twin bedroom. Wide windows frame the sea and fishing boats below.

Special Rooms give you separate areas for sleeping, sitting, and spending time together. The Masago-tei room combines a six-tatami Japanese room, twin bedroom, and ocean-view living room. The Nagisa-tei layout has an eight-tatami room, two low beds, and a spacious living area, while Hakusa-tei combines an eight-tatami room with a twin bedroom and living room.

The 45-square-metre Japanese-Western rooms have a six-tatami sitting area and a separate twin bedroom. You can relax on the tatami during the day and sleep on raised beds at night, making this a comfortable choice for a couple or family.

Traditional Japanese rooms measure around 30 square metres and have a ten-tatami layout. Low seating and futon bedding give you a simple Japanese stay, with the Pacific visible through the window.

Room equipment includes a television, empty refrigerator, electric kettle, safe, bathroom, washlet toilet, hairdryer, towels, yukata, slippers, toiletries, skincare items, and free Wi-Fi. Non-smoking rooms are available, while selected categories also include smoking rooms.

Dining

Dinner is served as a Japanese, Western, and Chinese buffet in the large Kanzuki dining hall. Seafood plays a leading role, with sashimi, sushi, grilled shellfish, and ingredients that you can combine to create your own seafood rice bowl.

At the live cooking area, chefs prepare crisp tempura and freshly cooked steak. You can also try pizza, pasta, salads, grilled dishes, and seasonal specialities. The selection changes during the year according to the available ingredients and current dining theme.

The buffet introduces you to local flavours through Katsuura tantanmen, a warming noodle dish linked with the town’s fishing community. You prepare the noodles and add your preferred toppings at the ramen area. For dessert, try soft-serve ice cream made with Bōshū dairy milk, along with cakes, pudding, jelly, and the chocolate fountain.

A lower buffet counter brings together dishes for younger family members. Baby food and tableware are also available for infants from around five to twelve months.

Dinner includes a self-service selection of alcoholic drinks and soft drinks. Beer, local sake, wine, cocktails, highballs, tea, coffee, juices, and other drinks allow you to choose what suits your meal.

Breakfast continues in buffet style with Japanese and Western dishes. You can prepare another seafood bowl with ingredients such as salmon roe and chopped seafood, or begin with dried horse mackerel, ochazuke, rice, and other Japanese favourites. Freshly baked bread, salads, yoghurt, fruit, and warm dishes provide lighter alternatives.

Onsen and Wellness

Hiten-no-Yu is the natural hot spring bathing area, set around 40 metres above the ground. Large windows look across the Pacific, allowing you to soak while watching the sky and sea change between afternoon, evening, and early morning.

The water is a sodium chloride and bicarbonate spring. Its mineral content is traditionally associated with easing muscle and joint discomfort, stiffness, sensitivity to cold, and general fatigue. The salt content also helps your body remain warm after bathing.

The men’s bath is on the 12th floor, while the women’s bath is on the top floor. Both are indoor panoramic baths; there is no open-air hot spring bath. A sauna is also available within the bathing facilities.

Mirable fine-bubble showerheads are provided in the washing area. The women’s powder room includes ReFa hairdryers and a shampoo and conditioner bar, allowing you to choose from several haircare products.

After bathing, visit the Daikan observation lounge. Large windows overlook the coast and fishing lights, while complimentary massage chairs give you a comfortable place to rest before returning to your room.

Aqua Palace is a separate swimsuit spa with indoor and seasonal outdoor areas. It is designed for swimming, water play, and spa-style relaxation rather than traditional naked bathing.

The indoor Action Spa Zone remains open throughout the year. You can float in a heated pool, sit against powerful water jets for a lower-back massage, enter a bubble pool, or stand beneath the five-metre waterfall. The area also has separate bathing spaces, low and high-temperature saunas, changing rooms, and a powder room.

The outdoor Sky Spa Zone opens seasonally and looks directly across the Pacific. Its facilities include a two-level open-air bathing pool, rock pools, a grotto-style pool, a bubble pool, a medium-temperature sauna, and places to sit between swims. The main outdoor swimming pool and illuminated night-pool sessions operate during selected summer periods.

Aqua Palace provides complimentary inflatable rings in playful designs, subject to availability. Children who still use nappies can enter the pool when wearing a suitable swimming nappy beneath their swimwear. There is no separate children’s pool, so close adult supervision is required.

Hotel Mikazuki Sea-Park Katsuura does not have a reservable private bath or family bath.

Guests with Tattoos

You cannot use Hiten-no-Yu, its sauna, or any part of Aqua Palace if you have tattoos. This restriction also applies when a tattoo is small or covered.

There is no private hot spring bath available as an alternative.

Facilities

The ocean-facing lobby provides comfortable seating, hanging chairs, and hammocks where you can pause with a view of the Pacific. Tea Lounge Shikisai offers another place to sit with a drink, although its operating schedule may change during seasonal events.

For indoor entertainment, Las Vegas has bowling lanes, billiards, medal games, and crane machines. You can also reserve a table at the Ping Pong area or spend the evening in a private karaoke room.

The second-floor children’s area provides colouring sheets, origami, and simple toys. Beside it, the comic corner holds around 2,000 books that you can read while looking towards the sea. A baby-care room includes a changing table, a women-only nursing room, and hot water for preparing milk.

The Hanaguruma shop carries sweets, food, and souvenirs connected with Katsuura and Chiba. A coin laundry is available for clothing, which is useful after swimming or a longer coastal stay.

Banquet halls range from smaller Japanese rooms to a large event space. Conference rooms can be arranged for meetings, organised groups, celebrations, and other gatherings. Massage treatments are also available when you want to relax after the hot spring.

In the evening, the illuminated fountain outside the entrance presents a short water show at scheduled times. Operating times can change according to weather and other conditions.

Activities

Begin your morning at the Katsuura Morning Market, which has continued for more than 400 years. You can browse vegetables, seafood, dried fish, handmade foods, and local products while experiencing the everyday character of the town.

Tomisaki Shrine is also within walking distance. Its long staircase rises above the streets of Katsuura and provides views across the town. During the Katsuura Big Hina Matsuri, the steps become one of the festival’s best-known displays.

At Katsuura Undersea Park, a marine observation tower descends beneath the surface of the sea. Through its windows, you can watch local fish swimming in their natural coastal environment.

Ubara Utopia offers walking paths along cliffs, coves, and wooded headlands. The route opens to wide views of the Pacific and shows a quieter side of the Bōsō coastline.

For a longer outing, visit Tanjō-ji Temple, connected with the birth of Buddhist teacher Nichiren, or continue to Kamogawa Sea World for aquariums and marine animal performances.

Inside the resort, you can spend your day swimming at Aqua Palace, bowling, playing table tennis, reading comics, singing karaoke, or enjoying the game centre. During summer, the beach and seasonal water attractions add more ways to spend time beside the sea.

Additional Features

Free Wi-Fi is available in the rooms and shared areas. You can store luggage before entering your room or after departure and borrow board games such as playing cards, UNO, Jenga, shogi, go, and Othello.

Family support includes children’s yukata, bed guards, baby-food heating, swimming nappies, nursing rooms, and baby-care spaces. Supplies and loan items are subject to availability.

Wheelchairs can be borrowed, and accessible toilets are available in shared areas. The building is not completely barrier-free, and the women’s hot spring bath on the 13th floor requires stair access from the highest elevator stop. Assistance can be arranged when climbing the stairs is difficult.

A reserved shuttle connects the hotel with JR Katsuura Station. Parking, a coin laundry, massage services, celebration cakes and flowers, and event spaces are also available.