India, July 29 -- Tucked away in a quiet corner of Goa is a historic villa that very few know of, and fewer still will ever get to step inside. Palacio Aguada is one of Goa's most exclusive luxury retreats, a private estate that's worth an estimated $100 million.

Overlooking the scenic Aguada Bay and offering sweeping views of the Arabian Sea, this ultra-exclusive retreat for the ultra-wealthy is built into the rocky hillside. Spread across five acres, it is an architectural wonder in red laterite that blends Portuguese, Moroccan and Mediterranean architectural styles with modern-day comforts.

The villa has 10 suites, along with several spaces designed for intimate celebrations. Curving staircases, vaulted ceilings, landscaped gardens a...