What can I do in Morocco in 16-18 days?

Sixteen to eighteen days is, for many people, the perfect maximum — long enough to see Morocco genuinely end to end, short enough that you keep your momentum and don't drift. At this length the grand circuit stops being a stretch and becomes the comfortable baseline, with several days left over to reach a sixth region the two-week trips have to skip. It's the closest thing to a complete Morocco without committing to a month.

I'd anchor it on the full north-south sweep at an easy tempo: Marrakech for three or four nights, the southern crossing through the valleys with a gorge night and two-to-three nights in the Sahara, north to Fes for two nights, on to Chefchaouen for two, and up to the northern coast — Tangier and Asilah — for two or three more. That alone is a magnificent fourteen-day spine, run slowly, with no day feeling clipped.

The extra two-to-four days are where sixteen-to-eighteen days gets to show off. The strongest options: a proper High Atlas trek of two or three days toward Toubkal with mountain gîtes and mule support; a push into the deep south — the Draa Valley's palmeries, Agadir, the Anti-Atlas — for a stretch of Morocco almost no short itinerary reaches; or a long, restorative coastal finish in Essaouira or Taghazout to let the whole trip settle before you fly home.

Even with this much time, the rule that matters most is rest. My firm guidance on any trip past two weeks is to schedule at least four genuinely unscheduled days, cluster the long drives so you're never in the car two days running, and accept that comprehensive does not mean complete — even eighteen days leaves corners of Morocco unseen. Plan for the slow days as carefully as the highlights, and you'll come home having seen almost everything and still feeling like you had a holiday.