Makar Sankranti is the only festival people from every community celebrate. In Mumbai at Dharavi , which is one of the most cosmopolitan and congested areas , celebrate this festival every year with zeal with Tamilians, Malayalees, Telugus  and Maharashtrians coming together to observe the event.   

Sankranthi marks the transition of the Sun from Dhanu rashi (Sagittarius) to Makara rashi (Capricorn). It also signifies the movement of the Sun from the inauspicious Dakshinayana to the auspicious Uttarayana, according to astral positions. Tamilians celebrate this festival for four days  as  Pongal Thiruvizah which  is strictly a rural festival. However Tamilians who have migrated to Mumbai also follow the tradition of  celebrating in the same manner. The name of the festival is derived from “ Pongal” – a rice pudding made from freshly harvested rice, milk and jaggery with cashew nuts added to it. 

At Dharavi area on Pongal day on Januuary 15 ,hundreds of  housewives gathered before Sunrise and boil the rice and milk in a pot and a turmeric plant is tied around it and it is then symbolically offered to the Sun-God along with other oblations. All people wear traditional South Indian sari and red thilak on their forehead.. The offerings include  two sticks of sugarcane in background , coconut , betel leaves, nuts  and  bananas in the dish. Many people also wear new clothes and women decorate houses with Kolam (designs) using rice flour and red clay.For Keralites, this is another important  festivals like Vishu and Onam. . Sri Ayyappa Bhaktha Samiti, at Dadar  celebrates this for three days since 1950 at Napoo Garden at Matunga. This year it concluded  on January 14 . Started by late Mr.V.Krishnan Nair this organization  has been conducting this festival which was then the first of its kind in Maharashtra . “We make  out of  banana stems , four temples ,which is  a replica of all the temples in Sabarimala in Kerala  and a mosque  of Vavar  ,a Muslim confident of Lord Ayyappa “ said his son Mr. Gopalakrishna Nair. In the evening a procession of Lord Ayyappa was taken out from the nearby Shiva temple with Velichapadu (Oracle) carrying sword and dagger which are the weapons of the Lord and led by Pancha Vadhyam and Nadaswaram he said.

While dates of all Hindu festivals keep changing as per the Gregorian calendar, the date of Makar Sankranti remains constant on January 14. After this event, days start becoming longer and warmer and chill of winter declines. It is believed that any auspicious and sacred ritual can be sanctified in any Hindu family, this day onwards. This is also traditionally the month of weddings. 
The Puranas say that on this day Sun visits the house of his son Shani , who is the swami of Makar Rashi. This day symbolizes the healthy relationship of father and son. It is the son who has the responsibility to carry forward his fathers dream and the continuity of the family. 
According to Hindu mythology, on this day Lord Vishnu ended the ever-increasing terrorism of the asuras (demons) by killing and burying their heads under the Mandar Parvat. Hence this occasion also identifies a period of enlightenment, peace, prosperity and happiness.

In Maharashtra and Gujarat, it is called Makar Sankrant and on this day people celebrates by flying of kites. The entire sky becomes a medley of colourful kites of various sizes and shapes. The Maharashtrians, on Sankrant day, exchange multi coloured ‘Tilguls’ made from sesame seeds, sugar or jaggery. 
In Punjab it is celebrate  as Lohri while  Assamese celebrate as Bhogali Bihu. In Uttar Pradesh, Karnataka and Bihar it is known as Sankranti and in Andhra Pradesh it is called Bhogi. 

On Makar Sankranti evening, at the hill shrine of Lord Ayyappa’s Sabarimala in Kerala , lakhs of pilgrims witness a celestial light. It is believed that this brilliant flame of light is the aarathi performed by the Gods. Known as Makar Jyoti, this miracle occurs at the time of the evening prayer time. This year it appeared on January 15.