India Jantar Mantar, Jaipur

Jantar Mantar (Magical Instrument) combines religion, science and art. It is the name given to a series of five structures built in Jaipur, Delhi, Ujjan, Varanasi and Mathura in the 1720s by Maharaja Jai Singh II. All together there are fourteen major geometric devices for measuring time, tracking constellations and even for observing planetary orbits. As it happened the Maharaja was not a very good observer and the Jaipur observatory was functional for only seven years. It fell into ruin and has been renovated many times. The main picture shows Samrat Yantra, the largest and most spectacular of the many instruments at the observatory. It is an equinoctial sundial consisting of a gigantic 27 metre high triangular gnomon. On either side is a quadrant of a circle parallel to the plane of the equator. The instrument was designed to measure the time of day correct to two seconds.

If you've seen Tarsem's The Fall, this is where the abducted bride ends her captivity; you'll recognize it.

Details for the main picture. 1/1500, f3.5, ISO200, 24mm equiv. f.l.

I was on a tour but taxis are convenient way of getting around.