Inside the small Soudamini Instruments factory in eastern Pune is what is claimed to be India's only miniature city, the lifelong obsession of model train enthusiast Bhau Joshi. In short, it's one of the world's great model train layouts, a detailed, fully functional and passionate display of mechanical and engineering wow.

　　It's the stuff of childhood dreams (and many adults, frankly). It features 65 signals, 26 points, fences, lamp posts and flyovers, a swimming pool, circus fairground (with roller coaster), drive-in theatre and dual carriageway with moving vehicles, among other bells and whistles, all controlled by a panel boasting 5km of wiring.