I like to walk, maybe a little too much, who knows. But I average about 150k-250k steps per month, more when on vacation.
After traveling a lot (and also having some minor injuries in the past - some SI joint irritation and also knee twist once or twice in my life) -- I think the best shoes are ones that have stability. Stability I think is essential when walking on cobblestone or other uneven surfaces or just for long times. Waterproofing is nice, but sometimes doing it yourself doesn't hold up well, and GTX shoes can be smaller or more rigid so you have to shop around. I've come down to these being the best ones (so far) that I've found. I'm in my 40s. I don't believe in being "fashionable" (sorry not sorry). Also the truth is no one cares about your stupid shoes when you travel, they are going to get dirty, just embrace it. I know the trend is for some brands to have really loud branding, and I get it, I don't like it either (HOKA staring at you!) but certain models its not as pronounced. I do think hiking boots are largely overkill in most situations you don't need those anymore unless you are planning on actually hiking in the mud or snow (maybe Norway trips!). But city trips with small detours to castles? Very unnecessary, clunky, and a relic of a time when we didn't have hybrid shoes or sneakers. Also boots tend to take more time to break in, and break ins mean blisters and suffering.
So here are my top picks:
Brooks Adrenaline GTS (support shoes) - any iteration prior to the 25s (the 25s attract dirt like a magnet -buy at your own risk - I also found them a tad too squishy with my back issues)
Asics Gel Kayanos (amazing very supportive the breathable mesh is nice). This is a Japanese brand (if you didn't know) and they run a tad small so try wide on if you normally don't wear a wide.
Hoka Transport GTX - gortex, it sounds like a flip flop I know, but they are great in dirt and on beaches if you want to just hose the sand off due to their waterproof material. The brown/beige ones don't have such grossly loud branding.
Saucony Hurricanes - less of a traditional stability shoe but still enough support to not twist your ankle or have pain later in the day.
And yes, they are more $$$ than maybe your daily shoes, but you don't want to have foot, ankle, hip ,or back pain when you are traveling. Brands like Sketchers might be cute, but the traction wears off within a week or two (been there done that).
And don't forget to bring a good pair of socks. I'm going to make a push to check out Darn Tough. Its a Vermont brand that has a lifetime replacement warranty. They are wool and made here domestically. Snag a pair when they go on sale on black friday or other major holidays. You won't be disappointed. They are well made, plush, and generally just as breathable as your regular cotton sock, but far more durable. Made for hiking, walking excessively, cold or warm weather.
Don't be afraid to try shoes before you settle on them. REI has an amazing return policy for members (obviously don't be crazy and constantly return things) but wearing the shoes for a week to see if they work is reasonable. They also generally have the best selection. Once you settle on a shoe you can buy it from them, then also check out places like Relay Goods (they sell returns from Pacers running store or just models that sat there for too long and are now out of season) for bigger discounts if you love a certain pair or model.
Generally your shoes are going to "die" between 300-500 miles. They loose their bounce, not just the tread. I know my parents used to just look at the tread and say "well its fine" but nowadays its more than the tread its also the sponge and repeated stepping squishes it down. My general advice is to take a pair of shoes that are mildly broken in on your trip - between 10-30 miles of use. As long as you aren't becoming a blister it should be fine.
Cheers :)!