More shoes! Lightweight sneakers with a good firm sole

I like the Merrell Glove line, though these are rather minimalist. I have rather squarish toes, and they seem to work for me. PS, I also wear Keens - Newport H2O.

I love my Cole Haan Grandpro Tennis Sneakers. They have good toe room, plus they are very comfortable. I wore them first when I traveled to Spain in October 2017. I wanted something comfortable, but that I could wear with a skirt. I loved them so much, I wore them to Italy the following June 2018 and then to London at Christmas. You can find more colors and better prices on Amazon.

You will do a lot of walking in Italy and Spain, so I hope you find the right shoe for you. Enjoy your trip.

I'd go with Allbirds Tree Runners - meets your criteria for lightweight, plenty of toe room, good sole, good for hot climates and a lot more fashionable and sleek than some of the clunkier trail shoes.

Another vote for the Allbirds, the " tree version" for summer (I love the wool version, too.) I wore mine daily for miles of city touring, as well as walking on gravel paths and various ramparts on castle ruins, etc. They stretch to deal with my bunions and generally gnarly old toes😄. The Keens would work for your more rigorous actual hiking.

If you like Keens, which I love because of their wide toe box, try the Keen Lorelai slip on. They are amazing right out of the box. I have also worn the Keen low cut hiking shoes and of course the Keen Newport water sandals.

Lems, Primal or mariner.

Lemsshoes.com

I am a solid fan of "On" shoes from Switzerland. Originally carried only by Fleet Feet in the U.S., they are now widely available. My husband had terrible plantar's fasciitis and a salesperson suggested On "Cloud" style (which comes in lace up or slip-on) because of the unique bottom of the shoe and the excellent interior shape and support. After wearing these shoes everywhere for about 2 weeks, his PF had almost disappeared, and we ventured out on the Rick Steves Eastern Europe trip, which includes some rigorous walking in city centers on cobblestones. He didn't have any problem with his feet at all. The PF is now a distant memory and we each now own multiple pairs. I can't say enough good things about them! They also carry running shoes, but I can't speak to those. About $130.00-150.00 in the US.

Wow, thanks all! Now I'm going to have trouble deciding! Now besides Keens, do most of these have a good, roomy toebox? I hate it when shoes "slope" (if I'm describing that correctly)--your feet slide forward when walking, toes hit the top, and you end up with toe pain!

Ah. I just read about "zero drop" shoes on the Lems site. This is what I was talking about--shoes that don't let your foot slide forward.

Roomy toe box: look at Altra

If New Balance works for your feet, take a look at the fresh foam arishi. I have a narrow heel but also need more room in the toe box and like a zero drop, non-clunky shoe. In general, I have found New Balance works great for my feet. I can walk miles and miles in these comfortably, they are super lightweight to wear and to pack, and I especially like the minimal markings and color offerings on their version 1's. I have the light gray and it goes with everything and has no bright or tacky logos. Amazon is a good place to purchase. I've been stockpiling the older version with the colors I prefer!

Merrell Gloves are roomy. My feet are not streamlined. They are rather square at the toe line.

I've also had good luck with Merrill. I've got duck feet- wide to box, and somewhat narrow heel, and a lot, but not all, of the lasts they use fit my foot shape well. They also do a lot of zero drop and true neutral models. I naturally walk on the outside edges of my feet, which is good knee and hip alignment, and a nice neutral shoe isn't going to mess that up like those labeled as stability or motion control do.

I'll just add that if you decide to go with a zero drop platform and you are not used to having no heel elevation you need to transition slowly. I wear the Altra Zero Drop which has a toe box similar to the Lems. Neither of those really have a firm sole, though. The minimalist shoes are designed to have more flex in them.

I'd suggest looking at Altra Lone Peak 4. They should come close to what you're looking for. The toe box is very roomy. The sole is shaped more like a foot than with typical shoes. If you look at some pics you'll see what I mean. These shoes are very lightweight and very breathable. The uppers are mostly made of an extremely fine mesh type fabric that breathes very well. The soles aren't super dense as they would be on a hiking boot, but this particular model is designed for trail running and it has a layer in the sole called a "stone guard" that stiffens it somewhat. It will spread the load if you were to step on a pointed stone as an example. I wear these shoes for hiking on rough trails regularly. As far as the "zero drop" I could take it or leave it. I don't see it as a big advantage or disadvantage. Others really like it. If there's a downside to this shoe it's the available colors. I've got the gray ones with orange trim, but none of them really suit me.

Just an update on shoes. I tried the Lems on but the person working in the store said I needed to give them at least a month. So I bought the Merrill Gloves which fit great and felt good walking on smooth surfaces...but, they were my heeNOT good on rocks, cobblestones, or any uneven surfaces. My feet felt bruised much of the time. I should have taken the advice to wear heel cups for a while, because my heels are very calloused now. Loved my Keens though! I'll still wear the Merrills but not for hiking.

Maybe you can just take some hiking boots

https://www.amazon.com/Skechers-Breathe-Fortune-Fashion-Sneaker/dp/B01HT93VBO/ref=sr_1_1?crid=GZ65E7EEB48Q&keywords=women%27s+sketcher+shoes&qid=1567186772&s=gateway&sprefix=women%27s+sketcher%2Caps%2C702&sr=8-1

These come in lots of colors and materials. Some more dressy, some more casual. My ex loved them for travel, she probably had six different pairs (or more).

My wife and myself wear Hoka Clifton’s and find them extremely comfortable and supportive for short or long walks! My wife has problems with her feet and these do the trick both of us! Will be wearing them in Europe again soon!

I would second the recommendation for ON shoes. I've just ordered my 3rd pair. My favorite are the Cloud line:
https://www.on-running.com/en-us/products/cloud/womens/sand

Very supportive, low profile, fashionable.

I recommend Ryka, wide toe box but narrow heel made on a women’s last. I wore a pair all over Southern Italy. Very comfortable, light weight and cushy. I just bought my third pair so I have more colors. They make several style but I found the Devotion Plus 2 to be the most comfortable for my problem feet. Ryka
I also like Alegria shoes but they discontinued my favorite Essence style, although limited sizes and colors are still available. Since they are leather, they are heavier shoes but have a wide toe box. Alegria Essence

I just recently picked up a pair of Ecco Soft 7 sneakers. They're very supportive and very comfortable. They would be great for walking around a city. They're casual type shoes and don't look like athletic sneakers. They are available for both men and women.

https://us.ecco.com/ecco-soft-7-m-430004.html?dwvar_430004_color=01001

The Sketchers recommended by Brad are the pair that I just wore on a three week trip to Turkey and Greece. Lots of walking, lots of cobblestones, lots of uneven ruins. They were very comfortable and I had no problems with them. I was somewhat surprised because they were brand new and I did not have time to "break" them in prior to the trip. They were great, right out of the box.