Kaancheepuram is a very important place.
(1) There are several important Shiv Temples there. There is one Prithvi Lingam there out of Panch Bhoot Lingam.
(2) There is one Devee Kaaamaakshee Temple also here.
(3) It is one of the three Kaashee of India.

Why is Kaancheepuram known as a Mukti Sthal?

There are seven Mukti Sthal in the country of India - Ayodhyaa, Kaashee, Dwaarakaa and Kaancheepuram. (see also Parashuraam Kshetra)
Kaanchi is a Mukti Sthal because Aadi Shankar attained Samaadhi here. Also, the seat of Goddess Kaamaakshee is located in this city. All the processions taken out by different temples during various festivals have to go through the streets of the Kaamaakshee Ammaan Temple. Hence, Kaancheepuram is a sacred town and a Mukti Sthal as well.

There are 3 Kaashee in 3 parts of Bhaarat -
(1) in northern part is Swarg =Tri-vishtap (Tibet) having Kailaash, place of Moksh.
(2) In central part (Bhuvar) it is Kaashee, the center of knowledge and the capital of Bhaarat in times of Devaasur wars and where Divodaas ruled.
(3) In southern part it is Kaanchee (Golden) which was centre of riches, called Dravid since the money (currency) flows like Drav (liquid). Now it is called liquidity of currency.

The Kaanchee Math is not recognized by other Math in Shringeri (Karnaatak), Dwaarakaa (Gujaraat) and Josheemath (UP). To say that the Kaanchee Math is not among the original Math is wrong. In fact this Math is the Mool Math or the main Math and all others are its branches. It was in Kaanchee that Aadi Shankar attained Mukti and also established the Chakra in the Kaamaakshee Ammaan Temple. Whether the Math is recognized by others or not, that doesn't matter much.