"town of villains") in pejorative relation to the conquest by king Philip II of Macedon who is said to have settled the town with 2,000 men who were false-accusers, sycophants, lawyers, and other possible disreputables., meaning "The Three Hills", and mentioned in the 1st century by Pliny.
At times the name was Ulpia, Flavia, Julia after the Roman families.
Although it was not the capital of the Province of Thrace, the city was the largest and most important centre in the province.
The ancient ruins tell a story of a vibrant, growing city with numerous public buildings, shrines, baths, theatres, a stadium, and the only developed ancient water supply system in Bulgaria. In 179 CE, a second wall was built to encompass Trimontium which had already extended out of the Three hills into the valley.
(39 sq mi), less than 0.1% of Bulgaria's total area.
It is the most densely populated city in Bulgaria, with 3,769 inhabitants per km². At the beginning of the 20th century, there were seven syenite hills, but one (Markovo tepe) was destroyed.
Summer (mid May to late September) is hot, moderately dry, and sunny with a July and August having an average high of 33 °C (91 °F). The average depth of snow coverage is 2 to 4 cm (1 to 2 in), and the maximum is normally 6 to 13 cm (2 to 5 in), but some winters coverage can reach 70 cm (28 in) or more. The days are mild and relatively warm in mid spring.
Plovdiv sometimes experiences very hot days which are typical in the interior of the country. Autumn starts in late September; days are long and relatively warm in early autumn. The average January temperature is −0.4 °C (31 °F). The average relative humidity is 73% and is highest in December at 86% and lowest in August at 62%.
On September 5, 2014, Plovdiv was selected as the Bulgarian host of the European Capital of Culture 2019.
This happened with the help of the Municipal Foundation "Plovdiv 2019″, a non-government organization, which was established in 2011 by Plovdiv's City Council whose main objectives were to develop and to prepare Plovdiv's bid book for European Capital of Culture in 2019.
Gentle winds (0 to 5 m/s) are predominant in the city with wind speeds of up to 1 m/s, representing 95% of all winds during the year.
Mists are common in the cooler months, especially along the banks of the Maritsa.
The city is in the southern part of the Plain of Plovdiv, an alluvial plain that forms the western portion of the Upper Thracian Plain.