There is currently, no technology that allows humankind to travel back in time. If such a technology were to be invented and released to the public at large, then society and civilization would be dramatically transformed. Time travel, particularly, historical time travel, would be one of the greatest and most fascinating adventures ever undertaken by humans. AT LAST, we would FINALLY have a truly, observable historical experience and the days of educated guessing and speculation based upon tenuous evidences, would be "a thing of the past".
However, even if such a perfect or near perfect technology were to come into existence, there are both ontological and even moral questions as to whether or not one should undertake such an awesome journey into the actual, tangible past.
Here's a THEORETICAL example: Let's say this fantastic historical time machine allows you to select any year in the past that you would wish to travel to-(from last year, to the time of Adam and Eve....about 6000 years ago) and let's say, you have always been interested in visiting Ancient Rome. While it would be much easier to plan a vacation to Rome during the summer months and take the expected sightseeing tours of The Forum, the Pantheon and the Coliseum, let's say, that such a summer tour, is just not fulfilling enough for you and that the ONLY WAY to ACTUALLY experience Ancient Rome, is to travel back TO....Ancient Rome-(via this new technology).
Ancient Rome's chronology began around 800 BC/CE and ended at around 500 AD/ CE; so you would have to select one year within a 1300 year timeline when preparing for your time travel visit. Would you want to see the founding of Rome in the year 753 BC/BCE, would you prefer to eyewitness-(via the time machine), the heyday of the Republic-(circa 300 BC/BCE) or if you wanted to visit and actually see the Roman Empire, would you want to visit Rome during the reign of Caligula-(37-41 AD/CE), Nero-(54-68 AD/CE) or visit the opening of the Coliseum in the year 70 AD/CE?
Should you choose to visit the Roman Empire, be prepared to enter an Imperial Dictatorship with FEW citizens, as well as a plurality of slaves and indentured servants with NO human rights. Blasphemy-(that is to say, publicly contradicting the presence of the Roman Deities), would be a crime punishable by death and a seemingly innocuous criticism of the Emperor and his regime, would also be a crime punishable by death. Executions in the Roman Empire, included, crucifixion-(usually along the Apian Way), as well as "being fed to the lions" in the Coliseum.
So the question is, would a contemporary Westerner, who has lived in a Democratic country (and Liberal Age) his or her entire life, be prepared to travel back to a distant, earlier age, time and place? An earlier age, time and place that was anti-democratic, as well as intolerant of religious and intellectual heterodoxies? The likely answer, is, no, you would probably not want to travel back to the Roman Empire, nor would you necessarily want to travel back to the more tolerant and relatively democratic Roman Republic either.
(A historical time machine would redefine the old term, "Culture shock" and its redefinition, would not be so benign or innocuous).
In other words, you wouldn't belong in the Roman Empire or even the Roman Republic. The time travel experience, would probably be too overwhelming and too complicated, as well as too emotionally and too culturally shocking for you to handle. Think about the chronological distance alone; you would be traveling back 1500-2800 years! BEFORE your time. Such a journey would be an incredible and memorable experience, though not necessarily a pleasant or enjoyable experience.
It would be better or wiser for one to plan a trip to Rome IN the year 2021....and NOT visiting Rome TO the year 221!-(either AD or BC).