It is believed that there is a presence of a water spring directly below the sanctum sanctorum which gives the hill its name.

According to legend, Saint Durvasa visited the Shiva temple at Kunnathur during his temporary stay at Kongu Nadu.

His mystic powers revealed to him that Modachur, a village near Gobichettipalayam, was the most suitable place for undertaking a penance on Lord Shiva.

[1] At Pachaimalai, Navagrahangal can be seen with their consorts seated on their respective mounts, which is considered unusual.The presiding deity of the temple is Sri Balamurugan in the form of Bala Dhandayuthapani.

Every month during the days of Visakam, Shasti and Kiruthigai, Abihekam, and special Shanmugarchanai are performed for the Deity.

In the first one, Lord Shanmuga and his consorts are adorned completely in white conveying that He is Brahma, the Creator.

Devotees worship by offering green flowers, clothes, and rose water to the Deity on that day.At Pachaimalai, Sri Kalyana Subramanya presides over the chariot festival held on Panguni Uthiram every year.

Kalyana Urchavam, the marriage ceremony, is performed for Lord Subramanya during Panguni Uthiram, Thai Poosam, and Kandar Shasti.

On the sixth day, Thiru Kalyana Utsavam is performed and the Sri Subramanyar graces the Wooden Chariot.

On Panguni Uthiram day, the temple is visited by thousands of devotees who carry Kavadi and perform abishekam.

The Deity, mounted on an elephant, presides over the function to defeat and give salvation to Soorapadman, the personification of Ego.

During the later part of the day, the presiding Deity of the temple graces in Thanga Kavasam–the golden Kavacha.

Shatru Samhara Thirisadai Archanai glorifies and invokes Lord Subramanya using the six syllables of Sa-Ra-Va-Na-Bha-Va in different arrangements.

Shatru Shamkara Homam is done in a grand manner at Pachaimalai during Vaikasi Visagam (birth star of Muruga).

Thaarabishekam is a vedic ceremony in which milk is dripped slowly on the Deity, through a Tharai or a Vessel.

The ceremony is accompanied by the recitation of Rudram eleven times, invoking Shiva as Rudra and Parabrama.

Hundreds of devotees can be found offering eleven Ellu Deepam, which is considered sacred to Lord Bhairava.