The historic Shaniwar Wada is an 18th-century palace fort located in the heart of Pune. Around 12 miles (20 kilometers) southeast of Shaniwar Wada, in the suburb of Wadki, is an extremely scenic lake.

In 1720, Bajirao Peshwa constructed the walls around the lake, which was once known as Wadki Talao (talao means "lake"). Later, the lake was renamed Mastani Lake (named after Mastani, the second wife of Bajirao Peshwa) because it is believed that Bajirao and Mastani visited this lake.

On the banks of the lake are two temples. One is dedicated to Lord Shiva (Mastaneshwar Temple), and the other to Lord Ganesh. Right next to the temples, visitors can see a flight of stone steps disappearing down a mysterious rectangular, underground chamber. On the stone is etched an inscription: "Shaniwar Wada Bhuyari Marg," which means an underground tunnel or passageway to Shaniwar Wada.

The stone corridor is narrow, cool, and damp since it is right next to the lake. It looks ancient and mysterious. According to sources and local folklore, the tunnel leads to Shaniwar Wada. The flight of old stone steps, the cool stone walls, and the overall mystery surrounding the tunnel look like something straight out of an adventure novel.