[Part 1] Traveling to Japan’s “Castles in the Sky” (2025):Explore Takeda, Akagi, and Tsuwano Castles

Japan’s “castles in the sky” are mountaintop ruins and surviving keeps that appear to float above a “sea of clouds” (unkai) on certain mornings. This natural phenomenon—when cool early fog fills valleys below—transforms ancient walls and towers into dreamlike visions above a white ocean of mist. Their dramatic vistas, historical legacy, and mysterious atmosphere make them perfect for a journey that feels like stepping into another world. Let’s start with three must-visit sites in 2025.
1. Takeda Castle Ruins (Hyogo Prefecture)
Known as the “Machu Picchu of Japan,” Takeda Castle’s extensive stone walls crown a 353 m mountain. When early morning mist fills the valleys below, the ruins appear to float in a white sea.
Best season for unkai: Late September to early December.
Best time of day: Just before and after sunrise (approx. 6:00–8:00 a.m.).
Best viewpoint for unkai:
●Ritsuunkyo Viewpoint (立雲峡) A 30–40 min uphill trail from its parking area offers the classic postcard view of the entire ruins above the clouds.
●Castle ruins themselves: Also magical in the mist, though you’re “inside” the cloud rather than seeing the full silhouette.
Access notes: Early start essential. Local buses are limited at dawn; driving or booking a taxi is recommended.
Tip: Local tourist sites publish daily unkai forecasts in season.
・Official Asago City Takeda Castle site (with unkai forecast info in season):https://www.city.asago.hyogo.jp/takeda/
・Look for 「雲海予報」 (unkai forecast) updates from around September–December.

2. Akagi Castle Ruins (Mie Prefecture)
A lesser-known gem deep in the Kumano mountains, Akagi Castle was built by the Kitabatake clan in the 16th century. Today, mossy stone terraces and dry moats remain, creating an untouched, meditative atmosphere.
Best season for morning mists: October to November.
Best time of day: Around sunrise (6:00–7:30 a.m.).
Best viewpoint:
●No formal viewing platform exists, but hiking the ruins themselves offers peaceful, elevated views over fog-filled valleys on clear mornings.
●It’s subtle and perfect for contemplative travelers who enjoy quiet exploration.
Access notes: Very remote—best reached by car. Trails can be slippery in wet weather.
Tip: Combine with the Kumano Kodo pilgrimage routes for a richer regional journey.
・https://www.kankomie.or.jp/en/
・https://kumano-kankou.info/en/

3. Tsuwano Castle Ruins (Shimane Prefecture)
High above the atmospheric town of Tsuwano—often called “Little Kyoto”—these ruins reward early risers with sweeping views over a sea of clouds. Originally built in the 14th century, Tsuwano Castle later expanded into an imposing mountain fortress with grand stone walls.
Best season for unkai: October to early December.
Best time of day: Sunrise (around 6:30–8:00 a.m.).
Best viewpoint:
●Castle Ruins: Accessible via a scenic chairlift (operates during the day) or a forested hiking trail. For unkai at dawn, visitors must hike up in the dark (about 45–60 min). The reward is a 360-degree panorama over mist-filled valleys and the quaint town below.
Access notes: Check local maps and trail conditions before a pre-dawn hike.
Tip: After sunrise, explore Tsuwano’s samurai district, historic churches, and local specialties like uzume-meshi.
Tsuwano Tourism Association (general visitor info):
https://tsuwano-kanko.net/
- While not a dedicated unkai forecast, local weather links and guidance are shared in season.

Which “Castle in the Sky” Will You Choose?
Each of these historic sites rewards early risers with breathtaking sea-of-clouds vistas. Stay in local inns for easier dawn starts, and immerse yourself in history, beauty, and hospitality waiting above the clouds.
Ready for Part 2? Next, we’ll visit Bitchu Matsuyama, Echizen Ono, and Gujo Hachiman Castles—more spectacular “castles in the sky” that promise unforgettable mornings.