The slope in the city interior varies from 8% to 25% depending on the location. Coastal areas are mostly more flat with a different slope that takes up less than 8%. The city is located right between the subduction zone of the Eurasia plate and Indo-Australia plate, making it extremely prone to earthquakes. The city was devastated by the 2005 Nias–Simeulue earthquake. The Meteorology, Climatology, and Geophysical Agency noted that on average, the city experienced more than 300 earthquakes per month on a varying scale. The city is also prone to tsunamis due to its coastal location.