Here's a nice article about Choquequirao & the planned "improvements" to get more tourists in.
www.theguardian.com/travel/2014/nov/01/peru-choquequirao-inca-ruins-trek

The super-classic, 100+ km Paine Circuit is the premier backpacking route in Torres del Paine National Park, Chile. It traverses some of the most spectacular scenery on Earth. The much shorter "W" is probably done more often as it covers much of the most best scenery of the Circuit plus allows close up views of the amazing towers & spires for which the Park is justly famous.

Note that there seem to have been some new regulations put in place that make it much harder to legally attempt an FKT, as reported by Sunny Stroeer (2/9/2018):

The Dientes de Navarino is an amazing route on Isla Navarino in Tierra Del Fuego, Chile. It is 54 km through some of the most rugged country you are ever likely to traverse. It is also considered the southern-most trek in the world, and from one place you can view Cape Horn. Wow!

https://www.bookmundi.com/t/dientes-de-navarino-trek-everything-you-need-to-know