Day 1 in London

Maybe one of the Hop On Hop Off (HOHO) Buses to get the lay of the land. Weather dependent, sitting upstairs and enjoying the fresh air. http://eng.bigbustours.com/london/home.html or https://www.theoriginaltour.com/#b

Or the British Museum, its Free. Take your time strolling around in it.

Enjoy your trip.

We had a similar day in London many years ago, as part of a "Day 1" of a "big-bus" type tour. Knowing nothing else, we splurged for a hop-on/hop-off bus. If you do just a wee bit of homework you'll travel on the same routes on the public bus and save $$$. Granted, the hop-on/hop-off buses have a live guide talking to you, open top, and no commuters. Either way, with limited time and being first time in London, a bus ride around town, specifically a route that passes all the major sites, would be a great thing to do. You can decided after one circuit, which stop you'd like to return to to spend more time perhaps later in the evening or afternoon.

Head to Greenwich on a riverboat RB1 from Embankment. From your hotel, take the Central Line Tube from Marble Arch to Oxford Circus, then Bakerloo Line to Embankment.

Head to the Pret a Manger at the corner of Oxford St and Great Cumberland Place and buy coffees and lunch if you're hungry.

Grab one of the HOHO buses that cluster near there. Sit up top in the fresh air, even if it's rainy or cold. :-)

Take a turn on the bus, get the lay of the land. Get off and see an outdoor sight if you want or just ride. Keep moving to thwart sleep deprivation.

Make it til 6:30, go have a simple meal and a couple of pints at a pub and then go to sleep.

This is really a question about how to handle jet lag on day one, a subject that's be beaten almost to death on this forum, try the search function above.

The most common advice, and what works for me, is to stay outside and keep moving around in the fresh air. The excitement of arrival usually powers me till around dinner time, then I have a nice meal with some wine and then collapse for what will hopefully be a long sleep till a normal wake time the next morning. An OTC sleeping pill helps.

I'd avoid long bus rides that afternoon. Ever notice how easily kids fall asleep in moving cars if they're tired? So will you. And I'd avoid museums that day for similar reasons. Outside, fresh air, hopefully sunshine, and blessed caffeine.

My sister and I walked around Bayswater, the neighborhood where our hotel was located. We also went to Kensington Gardens. Staying outside and moving around is a good plan. If you must take a nap, sleep for an hour or less. Even though I slept on the plane to Paris in April, I was a zombie by 1pm and needed a nap. After that, I was still tired but felt much better and more alert.

Check out the London Walks schedule for the day you land.

Walk Hyde Park to the Orangery - may be too much. Diana fountain?

Head in the direction of Buckingham Palace. Depending on the time of year, perhaps take a tour?

Head by Green Park to Piccadilly - walking. Same for Buckingham Palace. Stop at Hatchard's book store on way to Piccadilly.

Stroll over to Selfridges. Maybe eat there for lunch. Keep going till Regent's Street and take in Liberty.

Plot walk over to St. Martin's in the Fields and eat in the crypt. See Trafalgar Sq. on the way. Stop in National Gallery or National Portrait Gallery on the way. It is all about what you dream of seeing. It made my day one trip to see the portrait of Richard III.

Yep, HOHO bus was what I did on my first visit. Never can remember where I was except for Liberty which I wanted to see.

So, perhaps get a good map and guidebook and try to figure out what is within your tolerance - distance, time, stamina.

Of course, my first choice is always to take in a Globe matinee depending on the season. I can take in a matinee and make it back to the hotel and environs for dinner and then crash. You may also want to scope out the neighborhood. Will you want to find a supermarket? A take-out sandwich store? A pub? A news stand? An ATM?

Note, many of my suggestions are based on walking. And while I like buses and take the occasional tube trip, I found myself indulging in two taxi rides in one day during my last visit. It was all about what felt right at the time.

Map, guidebook, wish-list. What will make you happy and not too, too tired?

Enjoy.

Emma nailed it. Parliament Square then walk up Whitehall to Trafalgar Square or take Birdcage Walk through St James Park up to Buckingham Palace. A nice "I'm in London" walk for your first afternoon.