The pilgrims' walk from the shores of Lake Tana to Kristos Samra church is no more than a few hundred metres, yet feels like a 2000 year time-drop.
With their tall walking sticks, white cotton shawls and referential air, the pilgrims seem to have jumped straight out of a bible scene. Tiny papyrus boats offer to take us across a canal - some prefer to leap into the waters for impromptu baptisms.
The waterway is not the last obstacle on our quest; to reach the festival's 'inner sanctum', the area near Kristos Samra church, we have to zigzag up a steep hill, tip toe around hundreds of sleeping pilgrims and, on occasions, elbow our way in a very unholy manner through throngs of people.
Like the keenest of the faithful, I squeeze right through to the front of the church, get a blessing from the priest and gather some holy ash. I have to check my senses. Where is that devotional fervour coming from? Is it simply the power of mass emotion, or do I secretly hope that prayers made here are indeed invested with special powers?
Kristos Samra, Ethiopia's most important female Saint, is revered for having devoted her life to praying for others - including the Devil - and any plea passed through her to God is almost certain to be answered - apparently. I sneak in a prayer, feeling like a cheat.
I simply can't muster the kind of faith that renders the faces of those around me radiant with joy, as they observe the colourful procession of priests, bearing the church's copy of the Ark of the Covenant. And so I remain an observer - at one of the most mind-blowing rituals I've ever witnessed.
Katharina Kane travelled to Ethiopia on assignment for Lonely Planet. You can follow her adventures on Lonely Planet: Roads Less Travelled, screening internationally on National Geographic.