The arch was created by the erosion of volcanic rock, which is a common geological feature of the Banten coastal landscape.
The site offers direct visibility across the Sunda Strait toward the volcanic island of Anak Krakatau.
The beach surface is composed primarily of weathered coral fragments and volcanic debris rather than fine white sand.
Marine erosion continues to modify the shape and stability of the central stone archway.
Karang Bolong Beach is defined by a natural basaltic stone archway formed through centuries of marine abrasion. The coastal area features rugged volcanic rock formations extending into the Sunda Strait. Unlike sandy recreational beaches in the Banten region, this site is characterized by jagged rock pools and tide-sculpted stone structures. The arch itself acts as a geological window framing views of the sea and the distant silhouette of Anak Krakatau. Local terrain consists of hardened lava flow deposits covered by sparse vegetation. The beach lacks extensive soft sand, making it a destination for geological observation rather than traditional swimming. Visitors can navigate around the rocky protrusions during low tide to view the formation from multiple angles. It serves as a prominent coastal landmark in the Cinangka district of Serang Regency.
From the beach level looking through the stone arch toward the open ocean.
Wear sturdy footwear with non-slip soles as the rocky surface can be sharp and slippery.
Check local tide tables before arriving to ensure access to the arch is not submerged.
Bring sun protection as the rock formation offers minimal natural shade.
Attempting to swim in the areas with strong currents and sharp rock clusters.
Avoid climbing on the unstable stone arch to prevent erosion and personal injury.
