In 2015, this map became popular on one of our favourite subreddits.
It's from 1914, and depicts the time taken to travel a certain distance from London.
An update for 2016 showed that the scale has changed dramatically (from days to hours).
There really are very few places on the planet we can't reach within a day.
But where's the most difficult to get to?
This is the question the YouTube channel RealLifeLore recently attempted to answer.
They believed the answer would be in difficult environments. While submarines can take us to ocean depths, they believe the answer is one of the most treacherous mountain ranges.
They cite Muchu Chhish, a 7,453m high peak in the Western Karakoram mountains. The peak is highly inaccessible and, as far as is known, no-one has scaled it before.
However, Adventure Travel magazine suggest three others alongside it that could give the peak a run for its money.
Watch the full video below:
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