Being huge fans of Harry Potter , my daughter and I made an extra trip to King's Cross in search of the infamous Platform 9 3/4! We were so excited to be in London as the last Harry Potter film was coming out and to go see this! However, after going through a maze of hallways and construction, and asking attendants where it was, we were told to go look outside at the wall. I was a bit confused about this as I had seen photos that looked like it was INSIDE at between certain numbered platforms above or below a pedestrian walkway. So we go outside and find a PAPER LOOK-ALIKE glued to the wall outside of King's Cross Station that says Platform 9 3/4! It has a fake cart going into it. WHAT IS THIS???
Maybe because they've had too many people looking for it inside??? We were definitely disappointed and DID NOT take a photo - what a waste of tube money and time! Rubbish!

If you treat this place as a tube/train station, then..it is all fine: you have good connection with any part of the city, a lot of shops/restaurants in and around the station and the information centre is very useful and all the staff are friendly.
However, there might be a disadvantage for you that this place is always crowded and you have to be really lucky to take a seat somewhere. Plus the fact that during the major renovation process that takes place there's quite poor signage.

If you treat it as a touristic attraction (for the 9 and 3/4 platform or anything else) you'll be disappointed..There's hardly anything movie-alike in that place.
As I said before, there is a major renovation taking place and there is no such thing as the charming station that Kings Cross used to be.
The 9 and 3/4 platform is somewhere hidden in a tunnel..again, nothing interesting.
There are plenty of places in London where Harry Potter movie series was filmed except Kings' Cross..try there!

King’s Cross Railway Station seems to be in a permanent flux. I do not remember a single time when it was not full of scaffolding. It is currently getting a 21st century make-over which is long overdue, especially now that its neighbouring St Pancras is so posh and inviting.
Normally you can find a few shops and a huge number of commuters there. Do not ever go there for sightseeing at 8-9am or 4.30-5.30pm.
Tourists often have a look at the famous platform 9and ¾ of Harry Potter fame with a trolley stuck into it. I am not sure it is accessible at the minute with all the building works.
There is a travel centre and a metro station there with very good connection to all over the city. The British Library is also very close. If you need a quick bite and you have time before getting your train, I suggest you pick something up in St Pancras or on the street (there are a number of cafes and shops nearby).