He moved the capital out of Delhi for this reason

From Tughlaqabad to Daulatabad and back, traveler's tales describe Mohammed bin Tughlaq as unstable, a king to fear. Mohammed bin Tughlaq was a psycho. He was an extremely unpredictable character and borderline crazy. The Mehrauli-Badarpur highway, one of Delhi's busiest roads. Few know that it was built by kings who lived 700 years ago. In 1321, the road connected the Qutub Minar and the older city of Delhi to Tughlaqabad, the new fort of the Tughlaqs. Countless commuters pass the sloping, muscular fort walls. Few make the effort to enter. But Tughlaqabad is rich with historical detail. Its rulers had one of the largest kingdoms in Indian history. They were largely responsible for pushing back Mongol invasions from the north. Tughlaqabad was the main stronghold of their empire. And the Tughlaqs really controlled an enormous empire. They ruled from what's now Afghanistan right through the whole of Pakistan. Delhi was their center, which was, as today, a sort of megalopolis spread out over hundreds of miles with different centers and urban villages linking them all. This was the third city of Delhi to have been built. Its fort spans 6.5 kilometers across, with some walls rising to almost a hundred feet. The centuries have been unkind to some structures. But the tomb of the second king, Ghiyasuddin Tughlaq, is beautifully preserved. Ghiyasuddin may be remembered for his elegant mausoleum, but it's his son who really lights up the pages of history books. Some historians believe that Muhammad bin Tughlaq had his father killed to become sultan. He is remembered as a man who was, on the one hand, brilliant, and on the other, dangerously psychotic. One of the greatest accounts of the king's madness came from Ibn Battuta, a Moroccan traveler who worked at Tughlaq's court. Ibn Battuta's travels are now legendary. He set out on a journey of exploration from Tangiers in Morocco and reached Delhi in the early 1300s. In a series of journeys, Battuta covered more than 117,000 kilometers across Africa, Central Asia, the Indian subcontinent, Southeast Asia, and even reached China. Ibn Battuta witnessed terrible atrocities at Tughlaq's court. He mentions that almost every day there were prisoners undergoing some form of torture. Tughlaq had an insatiable appetite for cruelty and blood. For Ibn Battuta, it wasn't an easy job. His vivid accounts of Tughlaq's excesses exist even today. Ibn Battuta is very clear that Mohammed bin Tughlaq was a psycho in that he was an extremely unpredictable character and borderline crazy. He would find fragments of mutilated criminals lying in the forecourts of the palace. They had to walk through, you know, legs and arms and half carcasses every time he wanted to go to the audience hall. Even for a man like Ibn Battuta, who'd seen almost all the strangest sights of Asia, this was something that he considered a ruler who created a sense of unparalleled horror. Because of the threat of a Mongol invasion from the north, Delhi's population had swelled considerably with refugees. This pressured Tughlaq into taking a decision that he will always be infamous for. Mohammed bin Tughlaq decides to move part of the population from Delhi down into the Hindu heartlands of Maharashtra. Ancient Devgiri, near the modern day town of Aurangabad, was renamed Daulatabad, City of Wealth. It was to be the new capital. Delhi's population was given just three days to pack up and leave. In effect, Tughlaq had ordered thousands of families to walk about 1,200 kilometers south. Ibn Battuta gives a very tragicomic account of the expulsion of the population of Delhi and their journey to Daulatabad, and I really can do no better than to read his account of it. Majority complied with the order, but some of the population hid in their houses, and after the deadline had run out, the sultan ordered a search to be made, and his slaves found two men in the streets, one a cripple, the other blind. They were brought before him, and he gave orders that the cripple should be flung from a mangonel, and the blind man dragged from Delhi to Daulatabad, a distance of 40 days journey. He fell to pieces on the road, and all that reached Daulatabad was his leg. The travelers that could reach Daulatabad in one piece would have been met with an awesome sight. The fort rises out of the plains like a colossus, built on a mountain of hard basalt rock called Devgiri, meaning hill of gods. It is an intimidating sight, visible from miles away. It is a huge outcrop, so when you suddenly come across it, it's like a giant right in front of you. The element of surprise that it has when you first see it is what impresses you most. The highest point of the fort is almost 650 feet above the plain. It's one of the great fortresses of India. It is a natural fortress with three sides with very steep cliffs. The fourth side, the cliffs were artificially cut away, leaving almost vertical walls. It was designed to discourage attack. A moat was created at the foot of the hill. It was reputedly filled with crocodiles, yet another deterrent. Ibn Battuta was equally impressed when he reached it. He wrote it had, no equal in impregnability. The fort was originally built in the late 1100s by the first Yadava king, Bhilama, as his stronghold. Later, Alauddin Khilji took over, after which it came into the possession of Muhammad bin Tughlaq. One of the prominent landmarks inside is the Chand Minar. This was built after Tughlaq's time, when the fort belonged to the Bahmani sultans. This strategic fort changed hands many times over the centuries, going later to the Mughals, Marathas, and the British. The most secure point was the citadel at the very top. Here, its rulers, including Tughlaq, had a commanding view of the surrounding Deccan landscape. It is to this spot where the fort rulers would retreat to in times of danger. They made sure getting up was tough work. The single most astonishing thing is just simply to walk up to the citadel, and you go up zigzagging through these successive rings of walls and bastions with slits for boiling oil to be poured down on the incoming troops. Defensive positions were set up at different heights. A cannon from Aurangzeb's reign is believed to be one of the biggest of its time in India. The path gets steeper and narrower as you approach the top. Eventually, a dark door stands menacingly. Finally, at the top, you have these sort of strange troglodyte tunnels, some of which are deliberately made to be misleading. Only one leads up to the top. Muhammad bin Tughlaq's black labyrinth would disorient any invader. They are still eerie. 700 years ago, they would have been terrifying. There are interesting stories about it during the time when Ibn Battuta visited it, and he talks about a leather ladder that was used for accessing this inside citadel. Ibn Battuta, being the adventurer he was, would have explored the maze, scary as it may have been. It's probably around this time when Battuta writes of how his proximity to the Mad King was taking a toll on his nerves. He was afraid that Tughlaq would turn on him next. It was not long after that Ibn Battuta managed to escape the employ of Muhammad bin Tughlaq, and just in time, Tughlaq's insanity and bloodlust was to continue for years to come. As for Daulatabad, it did not remain the capital for much longer. Muhammad bin Tughlaq decided to return to Delhi, and order the citizens to start the long walk back.