How to find the best day tours while in a city?

Catherine.. most of us try and visit sites that are easy to visit on our own by public transport if we can.. but there are some sites that visiting via a tour may make it easier.. ( for instance we are visiting Dublin this july and I have already booked Mary Gibbons Highgrange tour online) .
I think you need to look at each destination,, decide what your sightseeing priorities are for each place,, then ask if they are easier to do on your own or take a tour.
For Paris I can't think of any site that a tour would be better for... everything is easy to do it yourself.. but many folks enjoy taking a Foxity tour or a hoho( L'Open Tour is decent enough for that type of tour) bus tour to get the lay of the land.. both can be booked ahead or when you arrive. Of course a lot depends on how much time you have in each place.. it sounds like you are running from place to place with just 1-3 days max in each place? That makes it even more important to decide your priorities.

Highgrange??? Dumfries and Galloway

Newgrange? Meath

All rock piles look alike. :)

One can easily spend 3 or 4 days in both Paris & London without a day trip. Yes - may of the popular tours sell out quickly or have ridiculous long lines to buy tickets once there. I would suggest you purchase your Eiffel Tower tickets online as soon as they go on sale. Buckingham Palace will also be open in August - fantastic - buy tickets ahead as well. One day trip from Paris is Versailles - also book ahead.
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Actually looking at your cities - the top 5 - and you are going during busy time - I would suggest you plan your days and purchase ALL tickets in advance that you can spend more time seeing things and less time in lines.

WOW ed.. so the pyramids are "piles of rocks "too huh.. and Newgrange is OLDER then the pyramids. Different strokes for different folks I guess which is why the OP must do some independent research and decide what THEIR priorities are.

In addition to seeing what people here say about various tours, I do read Trip Advisor reviews. I did a Mad Max tour from Bath to Stonehenge last fall and booked ahead as I saw that they are small groups and figured they might sell out. The tour was awesome (as were the TA reviews and RS's recommendations) and yes, it was sold out even with 2 of their small buses.

I, also, have booked a Newgrange tour with Mary Gibbons for June as I read they sell out too. I am slightly worried about this one as some of the TA reviews indicate she can be a bit boring and mechanical in her delivery. It wouldn't worry me if it were just me on the tour, but I've booked for 3 traveling companions as well and don't want them to have a less than optimal experience. She does have many, many excellent reviews and Rick mentions her in his Ireland guidebook so hoping for the best.

I think the thing with day tours is that you have to know it's a place that may be awkward for public transportation access and just take that as your baseline to manage your expectations.

Dearest Pat

I was politely trying to point out that you typed Highgrange when I'm sure you meant Newgrange.

I'm pleasantly surprised to see that anybody even knows what Highgrange is.

Ed: On Monday, March 17, I shall hoist a pint of beer that exhibits nary a trace of green food dye, in a quiet place well free of any pub waving shamrocks in the amateurs' eyes, and repeat your slogan: "All rock piles look alike."
Ireland is a pleasant land, isn't it? I shall go back; still lots of rock to see.

Or you could just get hooked on stone circles. Between the UK, RoI, and Brittany there's over thirteen hundred of the suckers. I haven't hit half yet and some of them are actually starting to look alike. I'll keep chugging away, however.

I would go to your big town library and see if they have RS Guide Books for the cities you are planning on visiting. If they do have any/some/all of them, look in each one for suggested side trips which are included in almost all of RS guide books. Take good notes. If your big town library does not have any RS Guide Books, go to a "progressive" books store and repeat the same search. You do not have to buy any of the books but if it were me I would buy them all. I go to Europe every summer for a month and while there take a RS tour (11 so far, #12 coming up in May - Greece) and I still buy his latest edition of guide books that cover where I am going. aloha

For London and day trips outside London, Sally Botwright is a wonderful tour guide. She has group or private tours. Her website is: sallybotwright.co.uk/Welcome.html

I would check tour companies on Trip Advisor, read their reviews, maybe come back and ask questions here on the forum about these companies and tours.

Hi Catherine,
Maybe you could share your interests/ passions with the board. That might help some of us steer you towards things that would be of most interest to you. Also, a rough idea of how long you're planning in each city. If you only have a few days in each city, it makes a difference how you allocate your time. I would say a Versailles trip would definitely be worth a day/half day out of Paris, but I'm not sure I would give up time in Florence to go to Pisa. In my experience, the best trips do sell out quickly, but don't give up.

I suggest you take a look at the website for Context travel. I've used them in all the cities you mentioned except Dublin, and have never had anything but a wonderful experience. They take very small groups, six people maximum on their group tours, and the guides are remarkably well educated and interesting. You can also arrange private group tours with them if you prefer that approach. They are a little more expensive than the large group tours, but are definitely worth it. Their walking tours usually last three or four hours, and they have some tours that are longer excursions.

One other thought… Whether a tour is worth it is only something you can decide. I can tour places on my own, and often do. However touring the Vatican with a PhD art historian who is a specialist Baroque art, touring the Italian Renaissance collection of the Louvre with a collection manager from the museum, etcetera, greatly enhances my travel experience and my appreciation of what I'm seeing. Also, I have learned so much. So when I'm visiting a city, I typically schedule one or two walking tours with Context Travel, and then I do the rest of it on my own. That mix works well for me.

We have always used Gray Line Tours, almost anywhere we have been. We took tours to Stonehenge, Windsor Castle, day trip around London (twice), day trip around Paris, Mont St. Michel, Normandy, Giverney, Versailles, Loire Valley, many tours in and around Rome, Australia, Switzerland, Canada, etc. We have always been happy with our tours. You can go to Gray Line Tours.com and see the available tours. Sometimes we have booked the tours before leaving home; other times we have booked them while visiting the cities. Gray Line Tours subcontracts their tours to local city companies. Evan Evans is used in London.