Pematangsiantar (sometimes written as Pematang Siantar, acronym PS or P. Siantar, colloquially just Siantar), and also known as the City of Pematangsiantar,[2] is an independent city in North Sumatra Province of Indonesia, surrounded by, but not part of, the Simalungun Regency, making Pematangsiantar an enclave within Simalungun Regency. Pematangsiantar formerly had the status of a second-level district (daerah tingkat dua) and was the administrative centre of the surrounding Regency, but in 1986 it was elevated to Kota (City) and separated from the Regency. Its population was 229,525 in the 2005 Intermediate Census, 234,698 in the 2010 Census[3] and 268,254 in the 2020 Census.[4] The official estimate as of mid-2023 was 274,838, making it the second-largest city in the province after the provincial capital of Medan.[1] Pematangsiantar is 128 km from Medan and 50 km from the renowned Lake Toba tourist centre of Parapat and is often a transit city for tourists who want to travel to Lake Toba and Central Tapanuli Regency. As a city that supports tourism in the surrounding area, the city has 8 hotels, 10 budget hotels, and 268 restaurants. There are still many old (1950s) model English-manufactured Birmingham Small Arms Company (BSA) motorcycles with a capacity of 500 cc used as Auto rickshaws which are recognized by their distinctive loud sound.