The train from Kandy via Nuwara Eliya is the famous approach — seven hours and worth every minute. Reserved seats sell out weeks in advance in high season; book through Sri Lanka Railways or a guesthouse. There are also direct trains from Colombo (around nine hours) and Badulla (one hour to the east).
By road, Ella is about 200 km from Colombo and roughly six hours by car. From the south coast, the route via Wellawaya and Diyaluma Falls is the prettier of the two options. Tuk-tuks meet every arriving train and can take you to outlying guesthouses in five minutes.