<Table> <Tr> <Th_colspan="2"> Cambridge International Airport </Th> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> <Ul> <Li> IATA: CBG </Li> <Li> ICAO: EGSC </Li> </Ul> </Td> </Tr> <Tr> <Th_colspan="2"> Summary </Th> </Tr> <Tr> <Th> Airport type </Th> <Td> Public </Td> </Tr> <Tr> <Th> Operator </Th> <Td> Marshall Aerospace </Td> </Tr> <Tr> <Th> Serves </Th> <Td> Cambridge </Td> </Tr> <Tr> <Th> Location </Th> <Td> Cambridge and Teversham, Cambridgeshire </Td> </Tr> <Tr> <Th> Elevation AMSL </Th> <Td> 47 ft / 15 m </Td> </Tr> <Tr> <Th> Coordinates </Th> <Td> 52 ° 12 ′ 18" N 000 ° 10 ′ 30" E ﻿ / ﻿ 52.20500 ° N 0.17500 ° E ﻿ / 52.20500; 0.17500 Coordinates: 52 ° 12 ′ 18" N 000 ° 10 ′ 30" E ﻿ / ﻿ 52.20500 ° N 0.17500 ° E ﻿ / 52.20500; 0.17500 </Td> </Tr> <Tr> <Th> Website </Th> <Td> cambridgeairport.com </Td> </Tr> <Tr> <Th_colspan="2"> Map </Th> </Tr> <Tr> <Td_colspan="2"> EGSC Location in Cambridge </Td> </Tr> <Tr> <Th_colspan="2"> Runways </Th> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Th> Direction </Th> <Th_colspan="2"> Length </Th> <Th> Surface </Th> </Tr> <Tr> <Th> m </Th> <Th> ft </Th> </Tr> <Tr> <Td> 05 / 23 </Td> <Td> 1,965 </Td> <Td> 6,446 </Td> <Td> Concrete </Td> </Tr> </Table> </Td> </Tr> <Tr> <Th_colspan="2"> Statistics </Th> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Th> Aircraft Movements </Th> <Td> 21,768 </Td> </Tr> </Table> </Td> </Tr> <Tr> <Td_colspan="2"> Sources: UK AIP at NATS Statistics from the UK Civil Aviation Authority </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Cambridge International Airport </Th> </Tr>

What is the length of the main runway at cambridge airport
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