one may sail the entire way around the world at what degrees and what latitude.?

Answer 1

There is some leeway, but the general answer is 60 degrees S latitude. This passes north of Antarctica and south of Africa, South America, and Australia.

In theory, you could also do the same thing at a latitude above 83 degrees, 40 minutes N (this would put you in the very high Arctic, which is typically considered permanently frozen ... but a submarine under the icecap or a ~really~ good icebreaker could maintain a circuitous course!).

Answer 2

I think in order to qualify as being a trip all the way around the world that you have to reach a point as many degrees N or S of the equator as where you start. 20 degrees N and O E (or W), for example you would need to reach 20 degrees south and 180 W (or E). In other words a point directly through the Earth from where you start, and then back.

Those people who don't even leave the Northern Hemisphere and claim their trip as "Round the World" are silly.

Answer 3

60 Degrees South. This is the only latitude where there are no continents as it is the Southern Ocean between Antartica and South America.