In many Jain temples you see a shankh (conch) carved on or near the entrance step. There are a few traditional reasons for this:

1. Symbol of a Tirthankar (Neminath Bhagwan)

- The lanchhan (symbol) of 22nd Tirthankar, Neminath Bhagwan, is the shankh. - Putting the shankh at the entrance reminds us that we are entering a Tirthankar’s place, and should go in with shraddha, shuddh bhav, and vinay (faith, pure feelings, and humility).

1. Leaving negativity outside

- In Jain temple architecture, certain figures are carved on or near the threshold to show that we should leave raag‑dvesh (attachment and hatred), paap‑bhav, and worldly worries outside before going in. - Stepping over/near such symbols is a quiet reminder: “Now I am entering a pavitra (pure) sthan, my mind should also become pavitra.”

1. Auspicious / protective symbol

- The shankh is used as a mangal (auspicious) chinh in Indian temple traditions. - At the entrance it acts as a good‑luck / protective sign, indicating: “From here onwards is a shayashya (merit‑giving), shant, and pavitra kshetra.”

1. Practical recognition

- At some places, special carvings on the first step/stone (like shankh, other figures) also help mark: - where not to keep footwear, - where to be more careful and respectful while stepping.

So, the shankh on the entrance step is not for worship of the conch itself, but mainly as:

• a symbol of Neminath Bhagwan,
• a reminder to leave bad thoughts outside, and
• an auspicious sign marking the beginning of a divya (spiritual) space.