It seems you’re referring to “Sundar Vav” (a stepwell). There are multiple places called “Sundar Vav” in Gujarat, and some are connected with Jain tirths where such vavs were traditionally built by Jain shreṣṭhīs (merchant patrons) to serve pilgrims with safe water. The exact builder and date depend on the specific location.

Please share the exact place (city or tirth) for this Sundar Vav so I can provide the correct builder’s name and period.