King's Cross St Pancras Underground station serves both King's Cross and St Pancras main-line stations.
It is in fare zone 1.
The station has two ticket halls, both of which can be accessed directly from the St Pancras concourse.
The tube station is served by more lines than any other station on the London Underground.
In 2018, King's Cross St Pancras was the most used station on the system, with 89.82 million passengers entering and exiting the station.

The Underground station pre-dates the mainline as part of the initial section of Metropolitan Railway project on 10 January 1863, which was the first section of the London Underground to open.
A separate station for the Great Northern, Piccadilly and Brompton Railway (now the Piccadilly line) opened on 15 December 1906, with the City and South London Railway (now part of the Northern line) opening on 12 May 1907.
The Metropolitan Railway platforms were moved to their current location in 1941.

The Victoria line platforms were opened on 1 December 1968.
A major expansion to accommodate High Speed 1 at St. Pancras opened in November 2009.

A pedestrian subway was built during the CTRL refurbishments.
 It runs under Pancras Road from the eastern entrance of the domestic concourse at St Pancras to the northern ticket hall of King's Cross St Pancras tube station (opened November 2009) and the concourse for King's Cross (opened March 2012).
King's Cross St Pancras Underground station serves both King's Cross and St Pancras main-line stations. It is in fare zone 1. The station has two ticket halls, both of which can be accessed directly from the St Pancras concourse. The tube station is served by more lines than any other station on the London Underground. In 2018, King's Cross St Pancras was the most used station on the system, with 89.82 million passengers entering and exiting the station.
The Underground station pre-dates the mainline as part of the initial section of Metropolitan Railway project on 10 January 1863, which was the first section of the London Underground to open. A separate station for the Great Northern, Piccadilly and Brompton Railway (now the Piccadilly line) opened on 15 December 1906, with the City and South London Railway (now part of the Northern line) opening on 12 May 1907. The Metropolitan Railway platforms were moved to their current location in 1941.
The Victoria line platforms were opened on 1 December 1968. A major expansion to accommodate High Speed 1 at St. Pancras opened in November 2009.
A pedestrian subway was built during the CTRL refurbishments.  It runs under Pancras Road from the eastern entrance of the domestic concourse at St Pancras to the northern ticket hall of King's Cross St Pancras tube station (opened November 2009) and the concourse for King's Cross (opened March 2012).
St Pancras railway station