London to Paris Daytrip

Considering that you will be very jet-lagged when you arrive, and transit through LHR is notoriously slow and tiring, yes, that's way too much. It could technically be done, but by the time you reach Paris, you'll be too exhausted to do much more than sleep. Getting up early enough to transit all the way back through London, then on to Stonehenge will obliterate you even before your tour begins. My advice? Recuperate when you reach the UK, and save your money and Paris for a trip of its own.

My short answer would be, yes, you are. Last spring did the overnite into LHR, HExpress to Paddington, Tube to King's Cross and then train to Darlington (York). Roughly the same time you're talking to get to Paris and I cleared customs at LHR in about 2 minutes (very, very rare - flight arrived at 0630). All I wanted to do in Darlington was take a shower and get the head down for a few hours. I managed a pub meal and a bit of a drive/visit with friends that evening but was not exactly the life of the party. Maybe would do it without Stonehenge and then there'd be a reasonable chance I wouldn't be a zombie when meeting the tour group. Good luck, oil the roller-blades.......

It sounds pretty exhausting to me. Have you already booked your flight to LHR or could you fly directly to Paris? I generally avoid travelling the day that my flight arrives in Heathrow; you cannot really predict if your flight will arrive on-time. Personally, I would not try it, particularly after an overnight flight. I'd save Paris for another time.

If you do decide to do this, I would plan a minimum of 4 hours between your arrival at Heathrow and departure on the Eurostar. You need to allow at least an hour to get through pass control and another hour to get from Heathrow to St Pancras. Also, you need to go through security at the Eurostar terminal so you need to check in 30 minutes before train departure.

If your flight is delayed and you miss your train, you will need to consider what options you have for changing your train ticket or getting a refund.

I also think this is cramming a lot in, but if you are set on a taste of Paris the best way would be to start your trip there, spend the night, and take the Eurostar into the heart of London the next day. In which case, slip Stonehenge, but even then only worth it if you handle jet lag well.

I note that you say 48 hours but from your description it sounds as though you only have about 36.

I understand what the other travelers are saying about being too tired to do it all. But I think it's a great idea to get a "taste" of a country or city even if it is for the day. I have done day trips to London and Dublin and it was great because then I know how to get around and where I want to go to next trip. That said because of the exchange rate I take a day trip tour of London and stay in Paris. But if you already have your tickets then I would sign up for a tour of Paris. That way you'll hit the highlights and the traveling will be easier.
Lots of Luck

I LOVE Paris, my favorite city in the world, and I would NEVER try and deter anyone from a visit there, even a very short visit, BUT, the way you have it planned is a problem. Too tiring. Ariving after a trans alantic flight, then the trip to Paris, then rushing back for a tour, and tours, btw tend to be tiring, as they go go go.

Either fly open jaw, into Paris, spend a day or two there, then go to London to meet tour, or save Paris for another trip.
You've paid alot for this tour , why start off exhausted.

Thanks for all the good advice. You're pretty much confirming what I thought...but my husband wants to see as much as possible since it's his first trip abroad. Since UA only allows one stopover or open jaw, and we're using that by landing in London and leaving from Dublin, I think I'll try to talk him out of Paris...unless we do it on day 2 and just meet up with our tour the morning of Day 3 which is just a morning bus tour in London, or Day 4 when we depart that area. Personally (and knowing my husband) I think that Day 2 to Paris just for the day would be best if he HAS to see Gay Pari'. I'll have to table MY desire to see Stonehenge (or Galstonbury moreso) and save it for another time. The one saving grace is that we are flying business class so we SHOULD be able to sleep on the flight over. Thanks Again! S-L

Ah, I am with your husband on this one, Paris is worth skipping Stonehenge a million times over, LOL

Have fun!

If you decide to go to Paris, my suggestion is that you decide in advance that you'll need to limit what you do in Paris on the day you arrive. Plan to spend a lot of time on your feet to fight jet lag--Paris is a great walking city--and then go to bed early (Paris time). Wake up refreshed the next morning and go as hard as you like all day. Give yourselves time to enjoy a leisurely dinner and take the last train back to London (21:13).

Shari, you said "Since UA only allows one stopover or open jaw, and we're using that by landing in London and leaving from Dublin, "

Could you land in Paris and leave from Dublin?