Pushkar is one of the oldest towns in India, built around a sacred lake and one of the few temples dedicated to Brahma. It is a small, calm contrast to Delhi, Agra and Jaipur. Adding it to the Golden Triangle takes only an extra day.
The route runs one way, ending with the drive from Pushkar to Jaipur airport, about 145 km (90 miles), so you do not retrace the road. Pushkar is a holy town, so meat, eggs and alcohol are not sold in the centre.