The Samrat Yantra is a huge sun dial. It can be used to estimate the local time, to locate the Pole Star, and to measure the declination of celestial objects. The Rama Yantra can be used to measure the altitude and azimuth of celestial objects. The Shanku Yantra can be used to measure the latitude of the place.
The largest instrument is the Samrat Yantra or equatorial sun dial. It consists of a straight 90 foot high ramp, or gnomon, which is aligned north soutn ahd elevated at an angle of 27 degrees above the northern horizon. The latitude of Jaipur is 27 degrees north, thus the ramp points toward the celestial pole. On each side of the ramp there are two quarter circles, or quadrants, fashioned in masonry. The quadrants are centered on the nearest edge of the ramp.