|Centuries:||1st century – 2nd century – 3rd century|
|Decades:||140s 150s 160s – 170s – 180s 190s 200s|
|Years:||167 168 169 – 170 – 171 172 173|
|170 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||923|
|Chinese calendar||己酉年 (Earth Rooster)
2866 or 2806
— to —
庚戌年 (Metal Dog)
2867 or 2807
|Coptic calendar||−114 – −113|
|- Vikram Samvat||226–227|
|- Shaka Samvat||92–93|
|- Kali Yuga||3271–3272|
|Iranian calendar||452 BP – 451 BP|
|Islamic calendar||466 BH – 465 BH|
|Minguo calendar||1742 before ROC
|Seleucid era||481/482 AG|
|Thai solar calendar||712–713|
Year 170 (CLXX) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Clarus and Cornelius (or, less frequently, year 923 Ab urbe condita). The denomination 170 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- The Suebian tribes of the Marcomanni cross the Danube and invade northern Italy. The Roman army (20,000 men) is destroyed near Carnuntum in Pannonia.
- The Marcomanni plunder Opitergium (modern Oderzo) and besiege Aquileia. This is the first time hostile forces entered Italy since 101 BC.
- Emperor Marcus Aurelius writes in Sirmium (Pannonia) his first of 12 books of the Meditations in Koine Greek.
- The Costoboci cross the Danube (Dacia) and ravage Thrace in the Balkan Peninsula. They reached Eleusina, near Athens, and destroyed the temple of the Eleusinian Mysteries.
- Marcus Aurelius orders humane treatment for Christians and slaves throughout the Roman Empire.
- An Equestrian Statue of Marcus Aurelius is erected in Rome.
Arts and sciences
- Marcus Cornelius Fronto, Roman grammarian, rhetorician and advocate (approximate date) (b. c. 100)
- An Shih Kao, Buddhist missionary
- Apuleius, Latin writer (b. 120)