Last I heard, the law in the UK was that pocket knives must e non-locking with blades under 3". Larger and locking knives can be carried if one can give a reason (self-defense is not acceptable) for carry. I think that as a tourist, unless you are going hunting or camping, you better stick to small slipjoints. I have been to the UK twice and I had no problems carrying a SAK Electrician.