Gavipuram is a locality in Bengaluru located close to Basavangudi.
It is known for Gavi Gangadhareshwara Temple.
Gavi Gangadhareshwara temple is a famous ancient cave temple. The temple is renowned due to a significant and almost magical phenomenon, that occurs in the temple every year, on a particular day in the month of January. Apart from the wonderful phenomenon, the temple also stands as a glaring example of the marvelous Indian rock-cut architecture. It is dedicated to the Hindu deity, Lord Shiva. The temple is unique from all other temples of Karnataka, due to the presence of two huge discs in the foreground of the shrine.
Another major attraction of the temple, is the presence of a rare idol of Agni, the God of fire. The idol has two heads, seven hands and three legs. It is perhaps the only temple in South India that has such an idol. The temple has a wonderful sculpture of Nandi (a bull). A beautiful image of Shakti Ganapathi, with 12 hands adorns the left side of the main entrance to the temple.
The history of the temple dates back to the 9th century. It is believed that the temple was cut out of a rock in the 9th century. It was used by the great sage Gowthama to perform penance. Later in the 16th century, Kempegowda I, the founder of Bangalore, revamped and extended the temple.
Kempegowda I
Kempe Gowda I championed the construction of several temples around the town, one of the earliest such temples that was renovated and constructed was the Gavi Gangadhareshwara temple.
The main idol of the temple is inside a cave that devotees descend into via steps. The inner sanctum of the temple is situated inside a cave carved out in the rock. Unusually for a South Indian temple, the complex is not aligned to any of the cardinal directions—it faces south-west.
In the forecourt stand two monolithic structures, named Suryapana and Chandrapana—each consisting of a massive disc atop a supporting pillar, like giant stone lollipops. Engravings of sitting bulls on the discs face each other. The discs are identical in size and have a diameter of about 6ft. Two of the pillars support huge discs that represent the sun and the moon.
The other two pillars have a trident (trishul) and a two-headed drum (damru), representing the two significant possessions of Lord Shiva. But the main architectural significance associated with the temple is the creation of the cave temple and the placement of the stone discs in such a manner that, they allow the sun to illuminate the Shivalinga for just one hour every year. In between the two discs there is a brass dhwajasthambha (flagstaff), and a small cubicle housing a statue of Nandi, Shiva’s bull mount.
A small flight of stairs leads one down to the cave that is hardly 6ft high; the height tapers off further into the shrine. In the cave temple the presiding idol, a Shiva linga, is surrounded by several smaller deities and sages, and the two pradakshine (circumambulatory) paths. Another statue of Nandi faces Shiva.
Every year on the 14th of January (Makara Sankranti), a rare and significant phenomenon takes place inside the inner sanctum of the temple. The rays of the setting sun on the western horizon, shoot a beam of light, that passes from under an arch, on the western wall of the temple, before moving towards the inner sanctum. It first lights the back of the statue of Nandi and passes over its horns and reaches the feet of the Shivalinga. Finally the beam of light illuminates the whole of Shivalinga.
This is a wonderful sight, as the event is marked by continuous ringing of the bells and chanting of mantras by the priests and devotees. The linga is bathed in milk by one of the priests during the entire period of the phenomenon. It seems as if the Sun is showing reverence to the Lord on the auspicious day. A large crowd of thousands of people gather from far and near and wait for hours to witness this magical event every year on the particular day that is also celebrated as Makar Sankranti. It is on this particular day that the dark interiors of the cave and the linga are illuminated by the rays of the bright sun for few moments every year.
Sunlight on Lord Shiva on Sankranti.
Devotees also believe that there are two tunnels, that extend from the inner sanctum of the temple. One of them proceeds towards the city of Varanasi in the northern part of India. The other extends up to another temple of Shiva with the same name, the Gangadhareshwara temple, located on the hill of Shivagange, about 10 miles from this temple.
1808 painting of Gavi Gangadhreshwar temple. Notice the watchtower on a hilltop in the background.
Please visit this temple when you are visiting Bengaluru.
I have finished my 500th answer in English Quora with this.