Is travelling Morocco end-to-end by train worth it?

I'm genuinely enthusiastic about train travel in Morocco, with one big asterisk about geography. Within the populated northern and central spine — Tangier, Kenitra, Rabat, Casablanca, Fes/Meknes and Marrakech — the ONCF network is one of the nicest ways to get around the country: comfortable, punctual enough, inexpensive, scenic in stretches, and blissfully free of the stress of driving. The Al Boraq high-speed line between Tangier and Casablanca is genuinely world-class and makes the north feel small.

The asterisk is that 'end-to-end by train' can't actually mean all of Morocco, and I'd be misleading you to imply it could. There is no train to Merzouga or the Sahara, none to Chefchaouen, and the deep south and the desert valleys are off the rail map entirely. The line south effectively ends at Marrakech. So a train trip beautifully links the imperial cities and the coast, but the desert — for many people the whole reason they came — needs a vehicle, whether a tour, a private driver or a rental for that leg.

Used for what it's good at, though, the train is a joy and a great value. Rolling from Tangier down to Marrakech over a few days, hopping off in Rabat and Casablanca, is relaxed, sociable and easy — you watch the landscape change, you don't fight traffic, and the fares are a fraction of private transport. Book first class on the busy legs for a guaranteed seat, keep some small cash for the odd onboard or station purchase, and you've got a low-stress backbone for the cities.

So my honest recommendation is a hybrid, and I suggest it to almost everyone who asks. Use the train for the city-to-city skeleton of your trip — it's cheaper, greener and more relaxing than driving those routes — and then add a guided desert excursion or a private driver for Chefchaouen, the gorges and the dunes where the rails don't go. That combination gives you the best of both: the ease of rail where it exists, and proper access to the wild, roadless Morocco where it doesn't.