Swimming in Segara Anak Lake is not allowed for trekking visitors. The national park prohibits swimming to protect the water quality of the lake and to maintain the fragile environment inside the caldera. Segara Anak is a volcanic lake with cultural significance, and the ecosystem around it is sensitive to pollution and human disturbance. Allowing hikers to swim would quickly damage the shoreline and the clarity of the water.
The lake is also colder than many visitors expect, and its depth drops off sharply in several areas. These conditions can make swimming dangerous, especially after long hours of trekking at high altitude. For this reason, the park directs all visitors to enjoy the lake only from the shore and to avoid entering the water.
While swimming in Segara Anak is not allowed, hikers can still relax at the nearby hot springs, which are one of the highlights of the three day trek. The natural pools sit close to the lake and offer a safe and comfortable place to soak and rest before climbing up to the Senaru crater rim for the second night. The hot springs are the area specifically intended for bathing, while the lake itself remains off limits for swimming.
