|Centuries:||1st century BC – 1st century – 2nd century|
|Decades:||50s 60s 70s – 80s – 90s 100s 110s|
|Years:||77 78 79 – 80 – 81 82 83|
|80 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||833|
|Bahá'í calendar||−1764 – −1763|
|English Regnal year||N/A|
|Chinese calendar||己卯年 (Earth Rabbit)
2776 or 2716
— to —
庚辰年 (Metal Dragon)
2777 or 2717
|Coptic calendar||−204 – −203|
|- Vikram Samvat||136–137|
|- Shaka Samvat||2–3|
|- Kali Yuga||3181–3182|
|Igbo calendar||−920 – −919|
|Iranian calendar||542 BP – 541 BP|
|Islamic calendar||559 BH – 558 BH|
|Minguo calendar||1832 before ROC
|Thai solar calendar||623|
|Wikimedia Commons has media related to 80.|
Year 80 (LXXX) was a leap year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Augustus and Domitianus (or, less frequently, year 833 Ab urbe condita). The denomination 80 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.
- Emperor Titus inaugurates the Colosseum with 100 days of games.
- The earliest stage of Lullingstone Roman villa is built.
- The Roman occupation of Britain reaches the River Tyne–Solway Firth frontier area. Gnaeus Julius Agricola creates a fleet for conquest of Caledonia, he finally proves that Britannia is an island.
- Legio II Adiutrix is stationed at Lindum Colonia (modern Lincoln). The city is an important settlement for retired Roman legionaries.
- The original Roman Pantheon is destroyed in a fire, together with many other buildings.
- The Eifel Aqueduct is constructed to bring water 95 km (59 mi) from the Eifel region to Colonia Claudia Ara Agrippinensum (modern Cologne).
- Gnaeus Julius Agricola begins his invasion of Scotland.
- Some 30,000 Asian tribespeople migrate from the steppes to the west with 40,000 horses and 100,000 cattle, joining with Iranian tribespeople and with Mongols from the Siberian forests to form a group that will be known in Europe as the Huns.
Arts and sciences
- Vologases II, king of Parthia
- Saint Timothy, bishop of Ephesus (traditional date) (b. c. 17 AD)
- Talhae, ruler of the Korean kingdom of Silla
- Paper I of Mathematics, JEE-2011 had a question paper of 80 marks