London 2 day itinerary

An Obvious one for you would be Kensington Palace for the Diana exhibit. Tickets must be purchase ahead of time (online). The Tower of London is a must see. A lot of the Museums are free such as the National Art Museum and the British Museum. Portebello Market is Saturday...early morning is best. The National Library is great for people who want to see a great antique books exhibit.
Greenwich Observatory. Kew Gardens. An easy choice is to take a River Thames boat ride to see London from the water: Parliament Buildings with Big Ben and Westminster Cathedral. A night at the Theatre...some discount tickets are available the day of the show. Of course there is too much to do in London so you can just do a walk about and when you get tired take the underground home.

With 2 days ( assuming full not jet lagged days) I would do:

• Tower of London
• Westminster Abbey
• St Paul's
• Churchill war rooms

and then I would walk and walk and walk :)

I would save the museums for another time

Sharon is correct to say leave the museums. You'll not be satisfied by trying to cram them in. She's also right in saying walk. Kensington is fairly central. You will more than able to all least walk by many if the sights

I hope you enjoy your first taste of London and plan to come back! The sights that have been suggested are good ones, obviously, but not if your interests lie elsewhere. There are no must-sees, only what you want to see. Be aware that on Sundays, both Westminster Abbey and St Paul's are closed to tourist visits but open for worship (and visitors are very welcome).

You might choose 2 days from Rick's 7-day suggested itinerary: https://www.ricksteves.com/europe/england/london-itinerary or at least use his suggestions to create your own 2-day plan.

Nothing says London like iconic Parliament Square.

Agree walking is the best way to see many of the sights as many are closer together than you think.

ALL within walking distance:
London Eye
The Thames
Westminster Bridge
Big Ben
Parliament
Westminster Abbey
Walk up Birdcage walk into St James Park up to Buckingham Palace. (please don't waste precious time on trying to see the Changing of the Guards)

Instead use your short amount of time visiting any of these Hyde Park, Kensington Gardens, Trafalgar Square, Covent Garden.

OR

See Tower Bridge, Tower of London and then walk up to the glass covered Leadenhall Market place and then a long but pleasurable walk along the Thames to the Blackfriar pub across the Road from the Blackfriar Tube stop and from there up to St Paul's.

Use Google maps satellite view to see how close things are and if you buy a travel card you can use the tube and busses to help tired feet.

Lastly if I were to see one interior that epitomizes London I'd spend some money and take the Verger's tour of Westminster Abbey. Utterly fascinating!

Enjoy your 48 hours. You won't be bored!

If you want to see inside Buckingham Palace, the state rooms are open from now until the end of September.

Just some ideas
here is a link with some info - too bad your only have 2 days......sorry

Things to do in London

Whether you have two days, a week or more, here is a different take for those who are looking for something besides the usual big sights -

From Anthony Bouradains Parts Unknown website -

A Perfect Day in London

Just found a great app -- Visit A City. It helps you sort sightseeing by proximity. You can put in Two Days in London and it sorts the top sites estimating how much time you'd spend at a site, showing how to get from one place to another. Really helps you figure what to do when.

These are some of the must see attractions in London -
Tower of London
London Bridge
Kensington Palace
Cruise of Thames river
Shakespeare's Globe exhibition
St. Paul Cathedral
Hop-on-Hop-Off London Bus tour
Churchill War rooms
London eye
Westminster Abbey tour
Stonehenge and Baths tour