The city of the sacred spring of Arethousa, Chalkis, built on the Euripus Strait, owes the etymological root of its name to the noun Halkos and to the metal processing workshops. According to Homer, Elephenor, king of Chalkis and leader of the Avantes of Euboea, is placed at the head of the forty ships, which the island's rulers contribute to the Achaean fleet that campaigns against Troy. It participates in the Second Athenian League, defecting in 446 BC, and Pericles himself, at the head of the Athenian Fleet, restores it to order. During the period of Roman rule, it is the major commercial center of the island. Byzantine Chalkis is fortified with walls and a moat. In 1204 it was occupied by the Franks and from 1216 it came under the control of the Venetians (Negroponte). In 1470 it was occupied by Mehmed II. Chalkida and all of Evia were surrendered to Greece in 1833.
Chalkida today, with a population exceeding 100,000 permanent residents, that is, half of the population of Evia, is ranked among the largest municipalities in the country and indeed with coherent metropolitan organizational characteristics between the city of Chalkida and the Municipal Units of Lilantia, Anthidonos, Avlida and N. Artaki. The new Municipality presents exceptional development potential in all three sectors of the economy, which allows for the complementarity of productive activities and the human-made environment.

The old bridge of Chalkida is an engineering marvel of purely Greek inspiration which constitutes the most central and emblematic point of the city. Chalkida is divided into two parts, one on the Euboean coast and one on the Boeotian coast, with the shortest part reaching approximately 40 meters. The first record of the existence of a bridge at the site is in 410 BC, when the people of Chalkida, after their withdrawal from the Athenian Alliance and fearing a naval blockade in retaliation, built a wooden bridge. In the Byzantine period and under Justinian there are references to a movable bridge that allowed navigation. With the arrival of the Venetians in Chalkida, the first significant change is the creation of the second branch of the strait when the intermediate islet was created and fortified. During the Turkish occupation, the construction did not change significantly, with the exception of the possible reduction of the openings due to additional embankments from both the Boeotian and Euboean coasts. In 1867, during the reign of Otto, with a project of exceptional technical and national importance, the first new bridge after the National Uprising was created. Due to the increased needs of both road traffic and navigation, an additional deepening of the strait to 8.5 meters was required, as well as a doubling of the width to 40 meters. The inauguration of the Italian manually rotating bridge took place in 1896, which served the needs of Chalkida and Euboea for approximately 65 years. In 1962, the current slide bridge was constructed by the Greek company BIO S.A., with a length of 42 meters and a width of 11 meters and has two traffic lanes. The maximum distance from the sea surface is 3.85 m. The bridge is managed by OLNE S.A.

The tidal phenomenon of Evripos in Chalkida is unique worldwide and attracts the interest of scientists and visitors. The narrow strait that separates Central Greece from Evia, connects the North with the South Evian Gulf and there the waters change direction approximately every 6 hours. This is mainly due to the Moon and the Sun, which with their gravitational attraction create tides, but also to the geomorphology of the channel. Thus, the current can reach very high speeds, up to 9 miles per hour, which makes the image of the phenomenon impressive. However, in some cases the change of direction does not follow absolute regularity, which makes it even more special. The phenomenon has occupied scholars since antiquity, such as Aristotle, but it is still a trademark of Chalkida, offering both scientific interest and tourist attraction.