Pekanbaru is the capital of Riau, a busy, hot, oil-and-trade city on the Siak River in eastern Sumatra. It is not as atmospheric as Bukittinggi or as famous as Medan, but it has a clear identity: Malay culture, river commerce, big mosques, markets, and a practical position between inland Sumatra and the Strait of Malacca.
Most travellers come through Pekanbaru rather than making it the whole point of a trip. That is fair. But if you have a day, the city gives you a useful look at urban Riau: the domes and wide grounds of An-Nur Great Mosque, the Malay collections at Sang Nila Utama Museum, and the trade buzz of Pasar Bawah.
The city is spread out and traffic can be tiring, so plan a compact route rather than trying to wander aimlessly. Add the Soeman Hs Library for architecture and local reading culture, then cross or view Siak IV Bridge to remember that Pekanbaru's story still runs along the river.