Types of Kumbh Melas take place at different times and locations

1. Maha  : takes place every 144 years comes after 12 'Purna Kumbh Melas' in Prayag only.
2. Purna  : takes place after every 12 years rotating through Prayag, Nasik, Haridwar and Ujjain one after another every 3rd years.
3. Ardh   : takes place in the 6th year after Purna Kumbh Mela.at Haridwar and Prayag
4. Magh : takes place annually only in Allahabad at the time of Jan-Feb, which is the Magh Hindu month, Except for the year in which Kumbh Mela and Ardh Kumbh Mela are held.

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The astrological positions of the different Kumbh festivals are as follows:

1. Prayag Kumbh: when Jupiter is in Aries and Sun & Moon are in Capricorn 
2. Haridwar Kumbh: when Jupiter is in Aquarius and Sun is in Aries 
3. Ujjain Kumbh: when Jupiter is in Leo and Sun is in Aries. 
4. Nasik Kumbh: when Jupiter and Sun are in Leo together. This event is called Sinhasth; hence, the Nasik Kumbh is also called SinhasthKumbh.

During this struggle between Demons and Demigods , various Demi Gods protected pot of nectar.

1. Chandrama (Moon) protected the nectar from spilling; 
2. Surya (Sun) prevented the breaking of the pot, 
3. Brihaspati (Jupiter) from being stolen by the demons, while 
4. Shani (Saturn) protected it overall

under Leadership of Indra. Therefore, the star sign in which these planets come together in a certain year, the Kumbh festival pertaining to that sign is celebrated during that year.