Obokekyo Mannaka is a hot spring inn situated directly above the Oboke Gorge in Yamashiro-cho, Miyoshi City, Tokushima Prefecture — a gorge designated as a National Scenic Beauty and Natural Monument of Japan. Standing at the confluence of the Yoshino River and its tributary Fujikawa Valley, the inn commands an extraordinary view of the crystalline schist rock formations, sculpted over 200 million years, and the clear waters of the Yoshino River flowing far below. Adjacent to the Oboke Gorge sightseeing boat landing, the inn serves as a central tourism hub for the Oboke-Iya Onsen region.

The main bath features simple sulfur spring water (hypotonic, weakly alkaline cold mineral spring) with a source temperature of 18 degrees Celsius, heated and managed through a circulation filtration system. The spring is indicated for neuralgia, muscle pain, joint pain, poor circulation, chronic skin conditions, fatigue recovery, and diabetes, and is reputed for leaving the skin remarkably smooth after bathing. The terrace-style open-air bath Seseragi no Yu uses artificial mineral water (Togol Warmtite) known for its skin-beautifying properties.

Day-trip bathing is available for 700 yen for adults and 350 yen for children from 12:00 to 16:00. Overnight stays include two meals featuring local Tokushima cuisine. A 90-degree sauna with self-service loyly and a cold plunge pool in the outdoor area are also available. The inn is approximately 20 minutes on foot from JR Oboke Station, with complimentary shuttle service for overnight guests upon advance request.