Modi posted about the event on Twitter.

On Mahashivratri, will be in Coimbatore to join the programme organised by @ishafoundation at the Isha Yoga Center. @SadhguruJV 

A five-tier security blanket has been put in place in and around the city, and along the Tamil Nadu-Kerala border, in view of Modi's visit.
With the venue being on the Western Ghats and close to the mountain ranges in Kerala, additional police personnel would be deployed along the state borders to prevent possible infiltration of extremists and Naxalites, police said.
The tight security was also being put in place in view of planned protests by human rights organisations, various political parties, farmers and tribal bodies, alleging that Adiyogi's face was built on encroached land and that Modi's visit would only regularise it (land).
In Chennai, CPM and CPI pointed to various alleged violations in setting up of the statue and said the prime minister should not visit the venue.
Modi is scheduled to arrive by 5:30 pm at Sulur airport and then leave for the venue by a helicopter.
First of the four planned statues
The Shiva statue in Coimbatore. Image courtesy: Twitter/@airnewsalerts
This is not to be the only one of its kind; there are also plans to have 112-foot-tall faces of Shiva in three other parts of the country — one each in the North, the East and the West, in addition to the one at Coimbatore.
"We want to place these tall faces of 'Adiyogi' in four corners of the country. The first one is in Coimbatore. The eastern one will most likely be in Varanasi. For the North, it will be somewhere north of Delhi, and there will be one in Mumbai as well," Vasudev told IANS over email.
Particulars of the statue
The face of the idol will be made of steel. Vasudev said, "The face is not just for aesthetics, it has geometric significance. A unique way of crafting a metal statue. We have essentially taken small pieces of metal and put it together. This is a very hard way to do it, but the most inexpensive. This is also unique — it hasn't been used elsewhere," he said.
According to one official, the structure is estimated to weigh around 500 tonnes.
An incredible engineering feat
"We took about two and a half years to design the face, but our in-house team built it in eight months. It is an incredible feat of engineering and has been done in a very unique way," Vasudev said. "It is an incredible feat in terms of time and engineering. We have done it on a small budget, in quite an ingenious manner. Also, we have made 'Adiyogi' in such way that it needs least amount of maintenance, which is important in the long-term."
Why is the statue 112-foot?
Queried about the significance of the figure 112 feet, Vasudev said, "Symbolically, 112 is a significant number, because 'Adiyogi' opened up 112 possibilities for human beings to reach their ultimate potential. For the first time in the history of humanity, He introduced the idea that the simple laws of nature are not permanent restrictions. If one is willing to strive, one can go beyond all limitations and attain liberation."
Vasudev also said there is also a scientific significance — there are 112 chakras in the human system, with which you can work, to explore 112 dimensions of life. "This face is not a deity or temple, this is an iconic inspiration. In pursuit of the divine, you don't have to look up, because it not somewhere else. Each of the 112 possibilities is a method to experience the divine within you. You just have to pick one," Vasudev added.
Largest statue face on the planet
In a statement, the Isha Foundation said that the statue's face will be largest in the world. The idea is not to build one more monument but to use it as a galvanising force towards self-transformation, it said. "This iconic face symbolises liberation, representing the 112 ways in which one can attain the ultimate through the science of yoga," the statement said.
Significance of Adiyogi
According to Vasudev, Shiva is not known as God but as 'Adiyogi' — or the first yogi, the originator of yoga — in the yogic culture. He was the one who first put this seed in the human mind, that one can evolve if one is willing to strive.
"For the first time in the history of humanity, He introduced the idea that the simple laws of nature are not permanent restrictions. If one is willing to strive, one can go beyond all limitations and attain liberation, moving humanity from assumed stagnation to conscious evolution," Vasudev said in the statement.
Yoga went throughout the world, not as a religion or a belief system or philosophy but as methods. Over time, there have been distortions, but still, unknowingly, millions of people across the planet are doing some yogic practice. "This is the only thing in the history of humanity that has lived for so long without ever being forced upon people," Vasudev said.
Describing the significance of Adiyogi, Vasudev said, "It is essential that the coming generations are seekers, not believers. As philosophies, ideology and belief systems that don't stand the test of logic and scientific verification will naturally collapse in the coming decades, you will see the longing for liberation will rise. When that longing rises, 'Adiyogi' and the science of Yoga will become very important."