What theme tours have you done, or do you aspire to do? I'm looking for ideas and inspiration.

Many bike tours have similar themes such as coast-to-coast, or following a particular coastline. I'm thinking about more unusual themes than simple geographic loop and A to B tours.

My unusual geographic theme tours:
Pedaling/hiking to 39 hot springs.
Pedaling/hiking to 25 waterfalls.

My unusual cultural theme tours:
11 national parks.
15 indigenous peoples' homelands.
Historic railway grades converted to recreational paths.
Historic silver and gold mining towns.

Next year I plan to do a cultural theme tour to 26 historic covered bridges. Beyond that I'm out of ideas.

What theme tours have you done? What do you aspire to do?
The more unusual and whimsical, the better.

Well, I suppose that many/most of the ACA mapped tours qualify as theme tours.  So I have done 2 coast-to-coast then (Transam and Northern Tier).  The Northern Tier is it's own theme I suppose, in that it traverses all of the states in the lower 48 along the northern border with Canada.  I have done the Western Express, which has as a theme that it at least sort-of follows along the old Pony Express route.  And many other ACA routes are also theme tours; Underground Railroad, Lewis & Clark, Southern Tier, Great Rivers South, Atlantic Coast, Pacific Coast, and Route 66.   Of these, the Underground Railroad and Route 66 might be considered to fit the "cultural tour" definition.

Wayne I don’t really have a good example a theme or unifying thread for a single tour, but I do have a loose theme for an ongoing series of tours. I have a goal to cycle from my front gate in Canberra (the national capital of Australia) to every other state capital city in Australia.

To date I’ve completed four of the possible six or seven total tours. I say six or seven because it’s debatable if Darwin is a ‘state capital’. It’d also be a very challenging ride. 

The other remaining two tours, Canberra-to-Brisbane and Canberra-to-Hobart should be relatively straight forward, though I might need a paddle/pedal boat for the Hobart ride. I’ll need cross Bass Strait somehow to reach the island state of Tasmania. 

I have one for you...

I have been thinking about this one for ages, and in fact more or less started it this summer but then stopped when I was feeling unmotivated...

This trip was to be called, "On A Mission" and I was going to visit all the still existing California Missions -  California Mission Map

I started it and visit a few but didn't finish.  However I may finish at some point...

Is this along the lines of what you mean by themed trip?

Graham, I like your multi-tour theme project. I would be lenient about what mode of transportation you use to cross the strait to Tasmania, but you would have truly heroic bragging rights if you got there by human power. And creative well-connected bragging rights if you cross the strait by wind power. Your state capitals project is similar to my multi-decade project to travel by bicycle in all 50 US states, completed in 2017.

In addition to multi-tour themes, it's also possible to do multi-theme tours. One of my favorite recent tours had 4 themes combined into one 13-day tour: Route 66, Grand Canyon, Navajo Nation, and red canyons.

Buddy, thanks for pointing out that many ACA routes offer ready-made themes. For sure the Lewis and Clark, Great Rivers, and Underground Railroad routes are unique and under-appreciated themes.

Karen, your California missions tour is an excellent tour theme. A long time ago I read a tour journal by a guy who did a California missions tour and offered to do work at each mission in exchange for the opportunity to sleep there. True immersion.

I'm still hoping to hear about people who did, or hope to do, truly one-of-a-kind themes.

I liked your hot springs tours for a great example of tour themes.

If you’re into sportsball you can try all the baseball fields, or football stadiums, or basketball arenas, or hockey arenas, etc. I think baseball is the only one you could ride to all venues to attend a game during its season, which is the rule.

If not sportsball, then maybe important historic sites, such as the California missions as Karen suggested. Don Weinell did the Oregon Trail, which was very well done (may still be up on the other site; his account was also published as a book). 

Volcanoes? High points of Oregon’s counties? Important Native American sites? National parks with the lowest visitation? I forget what the name of your hometown is, but you could ride to all the towns in the US with the same name. 

The second part of our first bike trip we followed the Mekong river from the northern-most part of Thailand to northeastern Cambodia, where we made an abrupt turn west. The following trip we met our old pal the Mekong in the delta region of southern Vietnam and crossed all of its many branches, sometimes on enormous terrifying bridges. But there is a section missing! And what about the headwaters in China? So our theme is “Unfinished business with the Mekong”, I guess.

I once came up with a crazy idea to start someplace in the middle of a mid-west or plains state (Iowa, Kansas, Nebraska?) and ride with the direction of the wind every day.  No matter which way they wind blows I would go that way until I got tired (though I suppose I could traverse over to different roads if the wind kept changing exactly 180 degrees ;-)

The Tailwind Tour maybe?

I doubt I will ever do it but coming up with crazy ideas is in my nature. ;-)

I love the idea of the Tailwind Tour! Mind you, I don't love the idea enough to actually do it myself, since it would only be practical in the checkerboard states, which are not my favorite places to ride. But if you do it, I'll definitely read the journal.

Ha ha.  Sounds like a challenge! ;-)

Actually I kind of like riding in the "flat, farm country" with the quiet roads and small towns.  Maybe someday....