VISIT VISAS
You can apply for a Standard Visitor visa if you want to visit the UK for leisure, for example on holiday or to see your family and friends, for business, or to take part in sports or creative events for another reason, for example to receive private medical treatment.
Except in the case of visa nationals, no entry clearance is normally required for a visit to the UK for up to 6 months. It is possible for non-visa nationals to arrive at a UK port and seek leave to enter from an immigration officer. It may however reduce any potential problems for those who are simply not tourists if entry clearance is obtained in advance.