the fourth century BC, Ujjain has enjoyed the reputation of being India's Greenwich, as the Prime Meridian of the Hindu geographers. The observatory built by Jai Singh II is one of the four such observatories in India and features ancient astronomical devices. The Simhastha mela, celebrated every 12 years, starts on the full moon day in Chaitra (April) and continues into Vaishakha (May) until the next full moon day. Mandu was originally the fort capital of the Parmar rulers. Towards the end of the 13th century, it came under the sway of the Sultans of Malwa, the first of whom named it Shadiabad (city of joy). It remained as the capital, and in it the sultans built exquisite palaces like the Jahaz Mahal and Hindola Mahal, ornamental canals, baths and pavilions. The massive Jami Masjid and Hoshang Shah's tomb provided inspiration to the designers of the Taj Mahal centuries later. Baz Bahadur built a huge palace in Mandu in the 16th century. Other notable historical monuments are Rewa Kund, Rupmati's Pavilion, Nilkanth Mahal, Hathi Mahal, Darya Khan's Tomb, Dai ka Mahal, Malik Mughit is Mosque and Jali Mahal. Close to Mandu is Maheshwar, a town on the northern bank of Narmada River that served as the capital of the Indore state under Ahilyabai Holkar. The Maratha rajwada (fort) is the main attraction. A life-size statue of Rani Ahilya sits on a throne within the fort complex. Dhar was the capital of Malwa before Mandu became the capital in 1405. There, the fort is in ruins but offers a panoramic view. The Bhojashala temple (built-in 1400) is still used as a place of worship on Tuesday. Dhar is also a birthplace of Raja Bhoj. Dhar people named as Dharwasi. Modern Indore was planned and built by Ahilyabai Holkar. The grand Lal Baag Palace is one of its grandest monuments. The Bada Ganpati temple houses what is possibly the largest Ganesh idol in the world, measuring 7.6 m from crown to foot. The Kanch Mandir is a Jain temple entirely inlaid with glass. The Town Hall was made in 1904 in the indo-gothic style; originally named King Edward Hall, it was renamed Mahatma Gandhi Hall in 1948. The chhatris are the tombs or cenotaphs erected in memory of dead Holkar rulers and their family members. The shrine of Hussain Tekri, built by the Nawab of Jaora, Mohammad Iftikhar Ali Khan Bahadur, in