The Kos Minars are the milestones made by the Mughal emperors between 1556 to 1707 AD. "Kos" literally means a medieval measurement of distance denoting approximately 3 km and "Minar" is a Persian word for tower. The Kos Minars measures over 30 ft and were once erected by the Mughals marking their royal route from Agra to Ajmer via Jaipur in the west, from Agra to Lahore via Delhi in the north and from Agra to Mandu via Shivpuri in the south. Modern highways have come up much along the same route as the one delineated by the Kos Minars. Abul Fazl recorded in Akbar Nama that in the year 1575 AD, Akbar issued an order that at every Kos on the way from Agra to Ajmer, a pillar or a minar should be erected for the comfort of the travelers. So that the travelers who had lost their way might have a mark and a place to rest. It is believed that Akbar derived inspiration to build Kos Minars from his predecessor, Sher Shah, who built many roads and repaired and revived the ancient route of the Mauryas henceforth termed the Sher Shah Suri Marg or the Grad trunk Road.
The Kos Minar is a solid round pillars that stands on a masonry platform built with bricks and plastered over with lime. Kos Minars became an institution during the rule of the Mughals that after Akbar, emperor Jehangir and Shah Jahan, both added to the existing network of Kos Minars. In the north they were extended as far as Peshawar and in the east to Bengal via Kanauj. The geographic span makes for nearly three thousand kilometers of Mughal highways, accounting for nearly 1000 Kos Minars, i.e., 1 every Kos or 3 km. there is no record as to how many of them have survived since then. The Kos Minars are never looked at as architecturally impressive structures. It is only when we view them in the totality of a much larger design that their real significance emerges. Some of the major cities of north India along with some of the most important historical monuments, battlefields etc. have come up on the route marked by the Kos Minars.
A network of medieval caravan sarai or inn or traveler's lodge has always been there from the Mughal times. A few of them still exist today. Besides, there are baolis or stepped-wells containing drinking water built beside some of the Kos Minars for the benefit of travelers. The Kos Minars proved critical in the governance, as there was a horse, a rider, a drummer posted at every Kos Minar and royal messages were relayed back and forth with great speed. Some historians believe that the Kos Minars were principally made to facilitate transportation and not communications. Those were the days when the Mughal emperors traveled on elephant back, in a royal entourage that included more than a thousand people consisting of bodyguards, personal retainers, tent erectors, cooks, foot soldiers and cavalry.
Whatever the reasons, the Kos Minars present a great travel story and it would indeed be a worthwhile exercise to check their present status. Lining the highway on either side, the most visible presence of the Kos Minars is between Agra and Delhi. What is interesting to note is that the modern highway is running almost on the same route as that of the Mughals. While the modern day highway goes past the Keoladeo National Park to Bharatpur, the Kos Minars take a more older and historic route via Bayana and Khanwa (where Babur fought with Rana Sanga). Between Agra and Jaipur, the Kos Minars run their parallel route along the highway, at least 15 to 20 kilometers in the hinterlands, coming closer as the road approaches Jaipur. While the highway goes straight through a hill pass into the modern city of Jaipur, the Kos Minars cross over the road to make their way to Amber. From Amber, the Kos Minars make their way towards Sanganer, an old town just south of Jaipur and finally meet up with the modern highway near Bagru, en route Ajmer. After making their presence felt on the highway with two quick appearances in succession, the Kos Minars cross over from the right to the left side of the road. A couple of kilometers from the road, they run their parallel course in the countryside, rejoining the highway just before Ajmer. Three kilometers away from the Durgah of Chisiti is the last Kos Minar on that route, which is located inside the bungalow of the Superintendent of Police.