The reason for naming the as Ananthapuri Express:
6123/ 6124 Chennai Egmore – Thiruvananthapuram Central
Thiruvananthapuram or Ananthapuri means “Abode of Lord Anantha” in Malayalam and Sanskrit. The name derives from the deity of the Hindu temple at the centre of the city. Anantha is the serpent Sesha on whom Padmanabhan or Vishnu reclines. The temple of Vishnu reclining on Anantha, the Sri Padmanabhaswamy temple remains the iconic landmark of the city.