Most curricula are shelves: content stacked in an order someone once found convenient. Al Bayan needed to be a journey, because its learners were travelling — from their first Arabic letters toward reading Quranic text with comprehension. We went looking for a metaphor that could carry that weight and found one buried in history: the Ottoman railway from Istanbul to Mecca.
A good metaphor is not decoration. It is load-bearing.
The railway solved problems we hadn't articulated yet. Levels became stations, so progress felt geographic rather than bureaucratic. Covers became cities, which gave the illustrators an inexhaustible brief. And arrival — Mecca — was no longer a grade. It was a destination the learner had been watching approach for four levels.
Test the metaphor before you board
Before committing, we forced the railway through every deliverable: Does it survive the spine of book six? The chapter dividers? The certificate of completion? A concept that only works on the cover is a poster, not a system. This one held everywhere — which is how we knew it was the one.