What do people like to carry in their Day Pack?

Depends on what you need during the day. Water is usually available on bus, glasses, meds, guidebook or torn out pages. I take a lightweight sweater in case a/c is cold.

It depends on what you are doing for the day.

When I am in cities, I usually don’t carry a daypack. I just carry a purse with the same things that I carry at home (phone, credit card, sunglasses, etc.)

If you are hiking, you will want raingear, water bottle, etc.

You can leave things on the bus. I will often pack the daypack with things I might need over the course of the day (e.g., raincoat, umbrella, water bottle, guidebook) but leave what I don’t need on the bus when we make a stop

Bandaids and Neosporin, and Compeed Blister bandages. Lip balm, hand lotion, sun block. Small items that can save your walking tour.

1) Granola bar/ Chocolate bar.
2) Small water, refillable.
3) Pouch with medication, band-aid, tried eyes drops, sun screen.
4) Wallet, ID. Obviously?
5) Phone + charger+ power bank
6) Pouch with a few personal higiene items (lady stuff).
7) Pen and small notebook. Surprisingly come in handy.
8) If fits-small Cola for digestion issues.
9) Umbrella, if the forecats requires it. Otherwise leave it.

I do very similar to Laura. The only time we took a day pack on that tour were our days in the Jungfrau/Lauterbrunnen region for hikes. A bottle of water, reading glasses, phone, mints, sunglasses. (We wore our coats.)

For any cities, we didn’t bring along anything different in Europe than walking around in the US, including we didn’t carry water bottles so no day pack needed for us in those places.

In addition to what others have mentioned, I have started taking a little picnic kit, for the times I pick-up food at a grocery store on stops.

I agree with the above: knifeforkspoon and some napkins can come in handy; folded up grocery bag; spare reader glasses; bandana;

Also, for just in case, some safety pins and a carabiner

Sunscreen.

It's also a place to carry things that you buy while out for the day - postcards, souvenirs, cans of soda, pastries, fruit, etc. That is, it works as a shopping bag too.

PS when you're in the mountains (Switzerland) the weather can change quickly during a day, so a rain jacket and an extra layer might be a good idea.

Depending on the weather and the planned activities, a pair of dry socks in a zip lock baggie. Saved the day a couple of times as few things are as miserable as having cold, wet feet.

I always have a small pack of flushable toilet wipes with me. I've learned that lesson the hard way: not all public restrooms in Europe have toilet paper available, or it's run out and not replaced. Also, a few euro coins to pay for public restrooms.

A small bottle of hand sanitizer too goes a long way.

As above, travel-size packs of Kleenex.

In addition to what has been mentioned I also carry a small bottle of hand sanitizer.

Interestingly on my first few RS trips the guide would pass out a pack of Kleenex on the first morning with the advice it could come in handy for other things. I used to think that was standard RS tour procedure but I just realized on my past 2 tours they did not do that.

I usually bring sunglasses, a lightweight weatherproof jacket, a wallet, and tissues, with other items depending on personal need.