Tṛṇabindu had three sons, named Viśāla, Śūnyabandhu and Dhūmraketu. Among these three, Viśāla created a dynasty and constructed a palace called Vaiśālī.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
विशालः शून्यबन्धुश्च धूम्रकेतुश्च तत्सुताः । विशालो वंशकृद्राजा वैशालीं निर्ममे पुरीम्
viśālaḥ śūnyabandhuśca dhūmraketuśca tatsutāḥ | viśālo vaṃśakṛdrājā vaiśālīṃ nirmame purīm
SB 9.2.33