Indonesia AirAsia flight QZ8501 was headed for Singapore from Surabaya, a city on the island of Java.
It lost contact with Indonesia air traffic control while flying between Belitung Island and Kalimantan on Sunday morning.
The search for the plane in the Java Sea is based on Pangkal Pinang of Bangka Island, and as of Tuesday, has expanded to include land searches.
Here's what we know about the places in the missing plane's path:
5.36am (Indonesia time) QZ8501 took off from Juanda International Airport in Surabaya.
The second largest city in Indonesia after Jakarta, Surabaya is the capital of East Java province. There has been rapid economic progress in the city of over 7 per cent a year since female mayor Tri Rismaharini took charge in 2010. The no-nonsense mayor picks up rubbish on the road alongside refuse collectors, and has been on a relentless campaign to clean up the city.
Flight QZ8501 lost contact at 6.18am (Indonesia time) over the Java Sea between Belitung island and West Kalimantan.
Fishermen on Belitung Island reportedly heard a loud bang that could have been the plane, Indonesia media reports said.
The island on the east coast of Sumatra has been known for its tin mines and pepper plantations - Mining firm BHP Billiton derived its name from Belitung.
But it also boasts white sand beaches and is developing as a tourist destination.
West Kalimantan is found on the island of Borneo, bordering Sarawak and and Central Kalimantan. It has a rich history, and is where the Lan Fang Republic set up by a group of Hakka Chinese miners from 1777 to 1884, was located.
Many of their descendants fled to Singapore after it was disbanded by the Dutch in 1884.
Search operations are based in Pangkal Pinang on Bangka island.
Pangkal Pinang, located on Bangka's eastern coast, is the capital of the Bangka Belitung. The province is the largest producer of tin in Indonesia, and Pangkal Pinang is also known as the capital of tin mining.
The industry drew large numbers of Chinese labourers since the 1770s, and there is a substantial population of Peranakan Chinese there.
Indonesia's National Nuclear Energy Agency was considering building the country's first nuclear plant in the province, which is about 1,960km to the south of Singapore.
Bangka Belitung is not in an earthquake-prone area, according to Indonesia's Antara news agency.
Sources: Straits Times Archive,Indonesia Tourism website, The Jakarta Post