If everything works out, I will be visiting and riding the Harz Mountain Railway in March of 2022. Not too many narrow gauge lines left on my bucket list.

To date, I've ridden:

Narrow Gauge:

Rio Grande Silverton branch - twice
D&SNG - took the kids
C&TS
Colorado RR Museum
G-Town Loop
White Pass & Yukon Route
Welsh Highlands Railway
Ffestiniog
Huckleberry Railroad
Tweetsie
Dollywood - interesting operation - 5% grade!
Central City operation mid-1970s

Standard Gauge:

Pikes Peak
Original Reader Railroad - mixed train
Texas State Railroad
Tennessee Railroad Museum
Black Hills Central
Numerous mainline excursions
Grand Canyon Railroad
Graham County Railroad
Mainline from Munich to Berlin
London to Caerfarnon Wales
City of New Orleans
KCS Baton Rouge to Shreveport repeatedly as a small boy before Amtrak

Bucket list to do:

Puffing Billy
Maine Two-footers - all of them
East Broad Top
Cass
Harz Mountain
Longleaf Museum
Roaring Camp and Big Trees
Yosemite

Pretty sure I've ridden more than I've listed, but that's all the brain can come up with at the moment. Checking off Harz Mountain will be a big one.