Also know, why is St Pancras station so named?
St Pancras International
London's most magnificent station and the surrounding area take their name from a Roman teenager, who was beheaded for converting to Christianity at a time when this was outlawed (c. 304 AD).
Secondly, are Kings Cross and St Pancras the same? King's Cross and St Pancras stations are two different stations, but they are side by side, separated by a pedestrian area and a road. They share a tube station (called "King's Cross St Pancras"). It is also the terminus for Eurostar trains to Paris and Brussels and for High Speed trains to Kent.
Then, where is the Thameslink station at St Pancras?
Platforms A & B: Thameslink platforms, platform A southbound to Croydon, Gatwick Airport, Brighton, platform B northbound for Luton & Bedford. Located underground and accessed by escalators down from the shopping arcade on the lower level.
Who built St Pancras station?
Waring Brothers