Jesus' disciples asked Jesus when "the conclusion of the system of things" would take place. (Mt. 24:3)
Jesus said: “Concerning that day and hour nobody knows, neither the angels of the heavens nor the Son, but only the Father.” (Matthew 24:3, 36)
BUT, Jesus did speak of future signs that would mark his presence and the last days:
“Nation will rise against nation, and kingdom against kingdom; and there will be great earthquakes, and in one place after another pestilences and food shortages; and there will be fearful sights and from heaven great signs.” (Luke 21:10, 11)
No one doubts that we are living in unprecedented times. Within one lifetime, one has seen horse-drawn carriages to putting men on the moon. Not one, but two World Wars have been fought and whether it is due to better technology and communications delivering more news from remote locations and/or the fact that there are more people to feel the effects - there has been an increase in reported earthquake activity.
One sign in particular that seems to be the key identifier for this specific time period:
“This good news of the kingdom will be preached in all the inhabited earth for a witness to all the nations; and then the end will come.” (Matthew 24:14)
Jehovah's Witnesses' message is about this kingdom. They are currently preaching about this kingdom in 236 lands:
Jehovah's Witnesses Worldwide Report (Fast Facts-Worldwide; WBTS)
...and their magazines, the Watchtower and Awake are the 1st & 2nd most widely distributed magazines in the world:
Watchtower and Awake are the most widely distributed magazines in the world (SFBT)
For more, see:
LAST DAYS (WOL; it-2 pp. 205-207)
Are We Living in “the Last Days”? (WOL; bh chap. 9 pp. 86-95 - Bible Teach (bh))
Are We Really Living in “the Last Days”? (WOL; w06 9/15 pp. 4-7)
The Last Days - When? (WOL; g 4/08 pp. 4-7)
More "Last Days" WOL search results