Is the Atacama Desert worth visiting?
Quick answer
Yes, on two conditions: that you give it at least three days, and that you understand you are paying for landscape and sky rather than for towns, food or nightlife. If either of those is wrong for you, it is an expensive trip to a place you will find empty.
The Atacama is not a cheap destination. You fly to Santiago, then to Calama, then transfer 100 km, then pay around $30 to $90 per excursion per person with entrance fees on top. For that you get landscapes and a night sky that genuinely have no equivalent anywhere else, and very little else. Whether that is worth it depends almost entirely on whether landscape is the thing you travel for.
What you are actually paying for
Three things that are hard to get elsewhere: the largest geyser field in the southern hemisphere at 4,320 m, a salt-and-clay landscape that looks like nowhere on Earth, and a night sky that a large share of the world's professional observatories were built to use. Nothing else. There are no ruins of consequence, no cities, and the beach is 300 km away over a mountain range.
The first condition: time
Three days minimum, and the reason is altitude rather than sightseeing. Visitors who allow two days do the low excursions and skip the geysers, or attempt the geysers unacclimatised and feel terrible. Either way they leave thinking the Atacama was overrated, and what was actually wrong was the schedule.
The second condition: what you want from a holiday
San Pedro is a small adobe town of about 4,000 people. The food is fine and expensive. There is no nightlife to speak of, because everyone is getting up at 4:30 a.m. If you need variety, a city, or a beach within reach, this is the wrong destination and no amount of scenery fixes that.
Who should not come
Anyone with heart or lung conditions who has not talked to a doctor about 4,000 m. Families with children under 9, who are not admitted to El Tatio at all. Travellers on a tight budget, because the per-day cost here is high relative to the rest of Chile. And anyone who does not actually enjoy looking at landscape, which is more people than admit it.
What it costs to get there
Santiago to Calama is a two-hour flight. Calama to San Pedro is 100 km and about $31 shared. Excursions run roughly $32 to $92 each, with entrance fees of CLP 8,000 to 15,000 collected separately in cash. Budget realistically before you decide.
The honest verdict
If you travel for landscape, it is among the best few places on the planet and worth the cost and the altitude. If you travel for anything else, spend the money in Patagonia or on the coast. It is a specific destination and it rewards people who want the specific thing it has.
Frequently asked questions
Is the Atacama overrated?
It is under-planned more often than it is overrated. Most disappointment traces back to two days instead of three, or to booking the geysers before acclimatising.
Is it expensive?
Relative to the rest of Chile, yes. Excursions run about $32 to $92 each, with entrance fees on top, and everything has to be flown or driven in.
What if I do not like deserts?
Then do not come. That is the whole product here, and there is no second thing to fall back on.