From the geological point of view, Isaccea is placed on the oldest land of the country. It is situated in the proximity of Danube Holm, on a rocky promontory 75-108 m altitude.

The region is characterized by a topoclimate with humid nuances which defines the climate of plain and holms. The year average temperature is 10°C; the year average quantity of precipitations is 450 mm. The mist is a frequent phenomenon due to the vicinity of Danube and fishing arrangements of Danube Holm. Movements of the air type breezes coming from the Danube and winds coming from northwest and northeast are predominant.