Giannitsa is the largest town and a former municipality in Pella regional unit, Greece. Since the 2011 local government reform it is part of the municipality Pella, of which it is a municipal unit. Its chief importance is as an agricultural centre - especially since it is 40 km from Thessaloniki. The former shallow, swampy, and variable-sized Giannitsa Lake or Loudias Lake (classical), south of the town, was drained in 1928-1932 by the New York Foundation Company. It or the surrounding marshland are sometimes called Borboros 'slime' or Borboros Limen.
Not far from the city are the ruins of ancient Pella, birthplace and capital of Alexander the Great. Giannitsa (then called Yenije) was an important center in the Ottoman period, and several important monuments survive: the tombs of Gazi Evrenos (a 19th-century substitute for the original) and Gazi Ahmed Bey, the Great Mosque, the Army Mosque, the hammam of Evrenos, and the clocktower, which have been declared historical monuments by the Greek Archaeological Service.