Mount Semeru erupts repeatedly; hiking trail closed through August for Hari Raya Karo

On 3 July 2026 Mount Semeru in East Java erupted seven times over four hours, with ash columns reaching 400 m to 1.4 km above the summit. The activity continued into 4 July, prompting the Center for Volcanology and Geological Disaster Mitigation (PVMBG) to maintain a Level III (alert) status and advise the public to avoid the southeastern sector of the Besuk Kobokan area, stay at least five kilometres from the crater, and observe a 13‑kilometre exclusion zone for potential hot clouds and lahars.

The National Park Authority of Bromo‑Tengger‑Semeru (TNBTS) announced that the Semeru climbing route will be temporarily closed from 7 August to 18 August 2026 to respect the indigenous Karo holiday. Hikers must descend by 16:00 WIB on 7 August, with the trail reopening on 19 August. Ticket bookings can still be made, and affected climbers may reschedule.

Local officials in Lumajang also debunked a viral social‑media video claiming a new eruption, labeling it misinformation. They urged residents to rely on official PVMBG data and avoid panic, emphasizing the ongoing alert and safety recommendations.