Karachi Circular Railway (abbreviated as KCR)   (Urdu: کراچی سرکلر ریلوے, Sindhi: ڪراچي سرڪيولر ريلوي) is a partially active regional public transit system in Karachi, Sindh, Pakistan, which serves the Karachi metropolitan area. KCR was fully operational between 1964 and 1994, until it was abruptly shutdown in 1999. Since 2001, several restart attempts were sought and in November 2020, the KCR partially revived operations on the orders of Supreme Court of Pakistan.
 With its hub at Karachi City station on I. I. Chundrigar Road, KCR's revived operations would extend north to Gadap, east to Dhabeji, south to Kiamari and west to Hub in Balochistan. The revived KCR operation is intended to become an inter-regional public transit system in Karachi, with an aim to connect the city centre with several industrial and commercial districts within the city and the outlying localities. Revival efforts of KCR had been proposed several times since becoming defunct in 1999 and remained unfulfilled mainly due to lack of financial and political backing. In May 2017, the federal government approved a Rs. 27.9 billion (US$97 million) restoration package for the KCR, however delays and disputes with the Sindh provincial government ultimately led to the cancellation of the funding.
 In August 2020, the federal government approved a Rs. 10.5 billion (US$36 million) rehabilitation package for the KCR restoration. The funding is slated to cover only phase one and phase two of KCR's restoration project, similar to the restoration of the Karachi-Peshawar Railway Line, according to Ameer Muhammad Daudpota.
 Karachi Circular Railway came into being during President Ayub Khan's tenure, who suggested the use of trains as a means for short travel in Karachi. KCR Operations began in 1964 under the administration of Pakistan Railways, with the aims to provide better transportation facilities to Karachi's growing population and outlying surrounding suburban communities. The original KCR line extended from Karachi City station and ended at Drigh Road station and carried 6 million passengers that year. Its instant success made Pakistan Railways a significant profit in its first year of operation. In 1970, KCR was expanded further east to Landhi Junction station while new track was extended westwards, thus opening Karachi Port Trust Halt station and Wazir Mansion station in 1970. Throughout the 1970s, track was further extended westwards and northwards towards North Nazimabad, forming a "loop line" which circled around several of Karachi's residential and industrial areas. At its peak, KCR ran 104 daily trains, of which 80 trains ran on the main line, while the remaining 24 trains ran on the loop line. During the 1990s, cost of operations increased while revenues dropped due to a deteriorating commuter service and increasing culture of fare dodging. Private transporters during this time also contracted KCR staff and by 1994 KCR was in incurring major losses due to mismanagement. As a result, the vast majority of trains were discontinued with only a few running on the loop. Unable to withstand the pressures of a growing transport mafia, Pakistan Railways abandoned the KCR in 1999. The official reason for the discontinuation was that Pakistan Railways was said to be making a loss by running the trains all over the city with few passengers taking advantage of the facility. Another version suggests that private transporters conspired with some corrupt staffers in the railways to fulfill their desire to bag the bulk of passengers for themselves The result caused instant gridlock on Karachi's streets. Severe criticisms were lodged at Pakistan Railways mismanagement as well as Karachi's "road transport mafia". In 2005, revival plans for the KCR were initiated to fulfill the growing transportation needs of Karachi, but never fully materialized. In 2009, the Karachi Urban Transport Corporation was proposed  in which KCR would be operated as a semi-autonomous body. Pakistan Railways would have 60% share in the corporation, Sindh government 25% and Karachi 15%.
 The KCR will consist of a loop line from Karachi City to Drigh Road via Liaquatabad. 44 kilometres will be revived with an additional 6 kilometre elevated dual track from Karachi City to Jinnah International Airport, allowing the KCR to connect to the Pakistan Railway main line. Existing railway tracks and 30 stations would be completely rebuilt on bridges. KCR would be used by 500,000 passengers/day which would increase to 1 million in later years. KCR will have 250 modern driverless electric bullet trains which would run 17-hours a day & 7-days a week. This project is also part of CPEC. Total cost of the project would be 294 billion PKR. The KCR would be run by the Sindh Government through Karachi Urban Transport Corporation (KUTC). Construction started in 2022 by FWO and would complete by 2025.
 
 
 Around 7,650 structures—including 4,653 houses—have been erected illegally, occupying 67 of the 360 acres of land required for the KCR.
 The KCR was originally designed according to the 1964 Karachi Master Plan, which had to be closed due to loss due to wrong route plan. Now it needs to make a brand new route plan which also separated from national railway line. That will help clear the busiest streets in Karachi.A large amount of criticism has been lodged at supposed "revival efforts" of the KCR. Countless studies and feasibility reports since 2001 has yielded no actual ground work. Several proposals were publicly announced by politicians both in the Government of Sindh and Government of Pakistan, all of which had approved plans and pledged funding. Yet each date passed by without any work commencing. The following is a timeline of statements made by several politicians over the past 15 years, all of whom boldly gave start dates for the KCR project. KCR was originally established in 1964 for: