The four mathas (monasteries or mutts) established byAdi Shankaracharya in the four corners of India were meant to uphold Sanatana Dharma(Hinduism).
It was also meant to propagate Vedanta
Shankaracharya Ashrams count amongst the most revered pilgrim destinations in the country
The heads of these four institutions are considered theprincipal Shankaracharyas in India.
The four mathas of Adi Shankara are:
Sri Sringeri Sharada Peetam in Chikmaglur in Karnataka
Jyotir Matha in the Garhwal region in Uttarakhand.
Kalika Matha in Dwarka in Gujarat
Govardhana Matha in Puri in Odisha.
Adi Shankaracharya was one of the most notable philosophers as well as Savants of India.
In his short lifespan of thirty-two years, he became one of the greatest teachers of the Vedas.
He was a major proponent of the Vedanta tenet that 'Lord Brahma and men are of one essence and every individual should try to develop this vision of oneness'.
As per him, God is one and the only way to achieve salvation is through the study of the Vedas.