The basic and most common object of worship in Shiva shrines is the phallus or lingam.
This form of the god can be traced back to the worship of primitive stone symbols as early as the neolithic period.
Already at Mohenjo-Daro the lingam occurs, side by side with other important symbols similar to those employed in later Hindu iconography.
it represents the generative male energy of the universe, and is symbolic of the great god Shiva.
Just as along the roads of Greek and Roman antiquity there might be seen images of Priapus at every field's end, in other words, practically everywhere, so in India today we may come upon those little cylindrical boundary marks, more or less ornamented, which are the lingas.
Shiva's lingam was also worn as a symbol by the Lingayat members of the Saiva sect.
The symbol continues to be venerated in various Hindu shrines and temples.
One of the most famous of these is the eleventh century Kandarya Mahadeva temple, itself part of the Khajraho complex in north-central India.
The exterior richness of this temple is complimented with over 900 carvings depicting various deities, demons, dancing girls, and animals.
The building was meant both as a dwelling for Shiva and as "a symbolic microcosm of the created world."
Its interior is somewhat darkened, as most Hindu temples are, but still decorated with intricate figures, mostly of an erotic nature, since Hindus hold that the sexual act symbolizes "the unity of the cosmos."
The congregation is forbidden to enter the Holy of Holies, known as the Womb House.
It was in this inner sanctuary that Shiva's lingam, constructed of marble, was housed.
The cosmic connection was then initiated when the temple was consecrated, during which a priest would climb to the top of the temple's highest pinnacle and "pierce" it "to create an aperture, representing the eye of the temple opening to the celestial sphere.