Eratosthenes is the Greek scientific writer, astronomer, and poet, who made the first measurement of the size of Earth. The Festivity includes a series of activities, designed for preparatory school students, revolving around the methodology used in measuring the Earth’s circumference 2000 years ago.

Eratosthenes Festivity has become an annual tradition that takes place every year on 21 June at the Bibliotheca Alexandrina, and on 20 - 21 June at the city of Aswan. On 21 June, the day of summer solstice, the 21st century school students conduct Eratosthenes’ experiment at the BA Plaza and in Aswan (Upper Egypt) to measure the circumference of the earth. Moreover, other countries around the world like France, Argentina, and Spain join the Festivity through the videoconferencing facility.

In Aswan, the Festivity comprises a fieldtrip to Elephantine island, interactive workshops, lectures, contests, and videoconferencing between Alexandria, Aswan and other countries to compare measurement results.