From San Francisco London is a 10 hour flight away. Not much when you say it fast. On a long flight like this make sure you get up and walk and stretch as much as possible and drink lots of water. This will help you to avoid getting swollen ankles and dehydrated. The long flight is worth the trouble as London is one of the best destinations to visit in the world.
Once at Heathrow Airport there are many ways to get into London. Your budget will drive which one you choose. But if you have a lot of luggage it is best to take a Taxi to Heathrow Terminal 1 and Taxi To Heathrow Terminal 2 or other road transport option. If you do not have much to carry then you might consider the London Oyster Card. It saves money when using the Tube, Trains, and Buses in London. It makes a £4 trip into a less than £2 trip. The train runs from the airport to many London locations. However, the London underground is a very old system with many stairs and no escalators and few elevators; so be prepared to climb stairs. The London Tube is not handicap ready. For example: To get to East London from the airport via the Tube can take the best part of two hours. Remember you might be extremely jet lagged, which will make carrying bags up and down stairs even more difficult, but the Tube with an Oyster Card will cost under £6; relatively inexpensive. And if you arrive London Southend airport and visit in London than you must hire London Southend airport transfer for getting any distance in London
While in London you must visit the British Museum. The Egyptian exhibition at the museum is excellent and a must see if you are planning to visit Egypt or not. Like all great world museums there are often transitory exhibitions. It was truly worthwhile to see the First Emperor exhibition where one could stand face to face with the soldiers of the Terracotta Army. This is not possible even in China.
A walk around Leicester Square, Regent Street, Covent Garden, and Nelson's Column are well worth your time too. It is in places like these you get a feel for the people and ambiance of London. The London Tower is really interesting. It is the home of the Crown Jewels, which are spectacular, but also it is a castle right in the heart of London, which is worth visiting its self. These days no visit to London would be complete without flying high above the city on the London Eye. You get magnificent views of the city from on high.
If you are interested in war museums and memorials then a visit to the war ship Belfast might be your cup of tea. Airport Taxi Leicester is a good option The Belfast had a distinguished career during the Second World War and Korean War. Moored on the Thames since 1971 she is worthy of a visit.
The Royal Observatory is where the zero meridian is located and so you can put one foot east of the zero meridian and one foot west of it at the same time. I am not sure what this really does for you, but it seems cool. To get there you can take the Thames ferry and get fantastic views of London from the river to boot.
These are but a few attractions waiting for you when you make your way to London. If you do not visit London before you die you will miss a truly amazing life experience.
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