Surabaya is Indonesia’s second-largest city and is less explored as a tourist destination despite its range of interesting sights and rich cultural heritage. Visit the house of Sampoerna,a heritage building that documents the origins of Kretek, Indonesia’s most popular clover cigarette. Climb aboard Kapal Selam, a Russian submarine kept for public display at the Monumen Kapal Samen. Surabaya is a perfect base for many one-day trips around East Java; the popular one is the Bromo Midnight Tour to see the majestic Mount Bromo, an active volcano in East Java. Watch the sunrise over the lip of the volcanic crater. Visit the Cheng Hoo Mosque, a pagoda-style mosque built in oriental architecture with vivid colors and carvings.