Map - Koidutown-Sefadu (Koidu)

Koidu Town (or Sefadu) is the capital and largest city of the diamond-rich Kono District in the Eastern Province of Sierra Leone. The population of Koidu Town is 124,662 based on the 2015 Sierra Leone national census. Koidu Town is the fifth largest city in Sierra Leone by population, after Freetown, Kenema, Bo and Makeni. Koidu Town is a major urban, business, commercial and diamond trade center. Koidu Town lies approximately 280 miles east of Freetown, and about 60 miles north of Kenema.

Two of the world’s ten largest and most famous rough diamonds were found in the Woyie River that flows through Koidu Town.

The city is officially known as Koidu City. The mayor of Koidu City and members of the Koidu-New Sembehun city council are directly elected every four years by the residents of Koidu. The current mayor of Koidu Town is Komba Sam of the Coalition 4 Change political party. Komba Sam was narrowly elected mayor of Koidu Town with 49.5% of the votes in the 2018 Koidu Mayoral election over his closest rival of the Sierra Leone People's Party. Politically, Kodu Town is not a stronghold of any political party, as the city is home to a significantly large support of both the Sierra Leone People's Party and the All People's Congress.

Koidu is one of the most ethnically and religiously diverse cities in Sierra Leone. The city is inhabited by significant numbers of many of Sierra Leone's ethnic groups, with no single ethnic group forming a majority. The Krio language is by far the most widely spoken language in Koidu Town and is the primary language of communication in the city. Koidu Town is the hometown of Sierra Leone's vice president Mohamed Juldeh Jalloh, Sierra Leone"s First Lady Fatima Bio and former Sierra Leone"s vice president Samuel Sam-Sumana; as all three of them were born and raised in the city.

In 1995 the government of Sierra Leone signed an agreement with the South African company Branch Energy Limited, a subsidiary of Executive Outcomes (EO), a business that supplied mercenaries to governments across Africa. The agreement, negotiated under the Mines and Minerals Act of 1994, was scheduled to last 25 years. Under it Sierra Leone’s military government gave the concession to operate the Koidu diamond mine to the firm in payment for helping to suppress the Revolutionary United Front rebels in the area during the country’s civil war. They had been using the diamonds to buy weapons and ammunition from Guinea, Liberia, and the Sierra Leone army. The government of Sierra Leone retained a 60% ownership stake in the Koidu mine.

The Sierra Leone Civil War ended in 2002. Records leaked from the Panamanian law firm Mossack Fonseca show that the family foundation of Beny Steinmetz family paid $1.2 million for half of the mining license issued by the national government for the Koidu mine. In 2003 the government transferred rights, duties, and responsibilities from Branch Energy to Koidu Holdings, a company owned by Octea of the BSGR Resources group, for $28 million. .