London restaurants and "must do"

I like to start with lunch at the National Portrait Gellery. The views over the rooftops of London remind me where I am.

These are all great suggestions--thank you all so much!!

Go to a performance at the Globe! And go to the Tate. Take the brown line on the Underground to Little Venice. If you adore gardens, take a train to Sissinghurst, Vita Sackville West's beautiful home surrounded by gardens that she designed. We stayed in a Homeaway.com apartment right on the Thames, and we walked to the Burrough Market every other day. I love Westminster Abbey, and hope it is on your list of places to visit.

So jealous!! I spent a semester in London and loved every minute. I definitely agree with having afternoon tea - at a swank hotel if you want the Downton Abbey experience, but if that's not your thing

Thanks, y'all! This is a great start.

Have one or more picnics, buying not only local produce but things like local cheeses that don't get exported (see Neal's Yard Cheese at Covent Garden or Borough Market)
if you like beer, explore real ale in pubs and shops (see picnic, above)
River Cafe for Italian and as a spur to the reinvigoration of British dining
Explore what's left or been uncovered of London periods you find most interesting (for ex, Roman; what's left of pre Great Fire London, 1666; Hampton Court for the Tudors & its great maze - a short trip out of town)

What to do:

Have a proper afternoon tea at either the Ritz or The Berkeley. It's pricey though. Or you can have tea at Fortnum & Mason and The British Museum which is a bit cheaper. Be aware that proper attire (i.e. no shorts, sneakers, t-shirts etc) is required at the hotels and some of the more fancy places.

You can also eat & drink amazingly well at the Borough Market.

Take a ferry to Greenwich and in addition to getting to the Prime Meridian, you get a nice ride along the Thames River.

Get one of a kind fashion at the Spitalfields Market.

Check out the London City Museum. Not nearly as crowded as The British Museum.

There's a good gelato shop called Scoop, located in Shorts Garden.

Despite the reputation of English food, the food in London is wonderful.

Never been, but always wanted to, eat at Ottolenghi

For great and reasonably priced Indian (Punjabi, I think), Tayyab in Whitechapel. Our AirBnB host recommended this as the best Indian in London over anything on Brick Lane.

I will try to think of some others. Gotta run to a meeting.