Hi there,
Thanks for your question, great to hear you're interested in King's and coming along to one of our Taster Days! Which Taster Day are you attending? For those being held at our Strand Campus, then yes Temple is the closest underground station, the following is an approximation of distance from surrounding stations:
Temple (District and Circle lines): 2 minute walk
Charing Cross (Bakerloo and Northern lines): 10 minute walk
Embankment (District, Circle and Bakerloo lines): 10 minute walk
Waterloo (Jubilee, Northern, Bakerloo, Waterloo & City lines): 12 minute walk
Holborn (Central and Picadilly lines): 12 minute walk
Chancery Lane (Central line): use exit 4 - 15 minute walk.
Hope that helps!