Best way to see country is via bus and the first class buses have bed like seats and you can see Nazca lines along the way and fly back via TACA Airlines to Lima. That does lessen chance of altitude sickness. And you will see spectacular scenery via air on way back. So romantic – the snow tipped Andes piercing the clouds.
As someone who’s done it, I like the bus. Of course, there are pros and cons of each.
Bus
Pros: A bus is cheaper, you get to see more of the countryside, interact with more people. You get breaks, get good seats (they have business class buses!), and you can stop off at places on the way. We stopped in Arequipa to go to the Colca Canyon, and in Nazca for a few hours to see the Nazca Lines.
Cons: It takes a long time. Some legs in the desert can be dull. Some people argue that it’s a dangerous road, but I’d say that’s maybe only in the mountains – the coastal road from Nazca to Lima is modern and high quality.
Plane
Pros: You get there faster. You get an aerial view. Save time.
Cons: It’s more expensive. You will not have a gradual introduction to the altitude, and may as a result get a bit of a shock when you step off the plane – it can be quite hard the first few days. You’re stuck in a cramped economy class seat. You don’t get to interact with many people.
Hopefully that helps. Personally, even though I bused last time, if I had the time, I’d bus again. I disagree with @vartec – the choice is not obvious, and I loved the bus trip. But you must make that decision yourself, of course 🙂
Bus ride from Lima to Cuzco is 20 to 21 hours depending on the company, costing from $65 for one-way ticket. And it’s also mainly less-than-safe mountain road.
Flight from Lima to Cuzco is 1h10m to 1h25m and you can get ticket as cheap as $175 for round-trip.
Credit:stackoverflow.com‘