From Bangkok to Ayutthaya

By Bus
Buses frequently depart from Bangkok Morchit bus terminal.
Mini vans leave from Victory Monument.

By Train
Local trains leave from Bangkok Hua Lamphong every hour with no reservation required. Journey time approximately 1h45m. Fare 15 baht.
Air-conditioned express trains take approximately 1h15m and leave less frequent. These require a reservation to be made.