Any recommendations on a 1 day Loire Valley castle tour?
Where will you be starting from? Do you want recommendations for a tour from Paris? From somewhere in the Loire Valley? Somewhere else?
If you are in Paris my suggestion would be to take an early train to Tours and arrange to pick up a tour from the train station there. You can google for "Chateaux tours from Tours" or do a search here as there have been some recommendations. Or you can search for a tour from Paris but that can involve a lot of bus travel time that I personally prefer to avoid (I'd rather use the train for the major distances).
There is a company in Tours called Quart de Tours. As I look them up again, I see they're now "all inclusive" - they used to just take you to the chateaux and dump you off - now they include transportation, entrance fees, and sometimes audio guides and lunch. Seems like they stepped it up! In general they include 2-3 chateaux per visit at around 125-150EUR. They leave from the Office de Tourisme in Tours which is an easy walk from the train station.
Are you staying in the region for 1 day or visiting from somewhere else? Tours would be a great city to spend the night. You'll be exhausted after covering the chateaux, but you can go to Place Plumereau and see the gorgeous old architecture or go to the guinguette on the Loire and have a drink.
***Note, the first option says "liberty lunch in Chenonceau" ---looks like a very poor translation but means you get free time for lunch in Chenonceau.
I like the idea of a Liberty Lunch in Chenonceau!! Maybe a little Franco-American harmony . . . etc etc
I thought it sounded pretty charming, too, Kim! haha!
12 hour bus tour https://www.pariscityvision.com/en/audioguide-loire-castles-tour
Many other choices at https://www.pariscityvision.com/en/france/loire-valley-castles
I took the 12 hour tour in April and it was great.
In 2014 I did a tour through Viator Tours. Skip the Line: Chateaux de Chambord, Chenonceau & Loire Valley Wine Tasting tour: https://www.viator.com/tours/Paris/Skip-the-Line-Chateaux-de-Chambord-Chenonceau-and-Loire-Valley-Wine-Tasting-Day-Trip-from-Paris/d479-3731LOIRE. Viator is a third party, I believe the actual tour company I was with was either, Paris City Vision or Gray Line Tours, not 100% sure.
I enjoyed the trip, I went the first week of October and the leaves were changing color. Ended up meeting 5 people who lived nearby me. Small world.