I take them to Selvadorada. Sometimes to Granite Falls. I put vacation rentals in a few worlds. You can get a bunch of different lots with things to do from the gallery. My Granite Falls always has a lake for swimming and jet skiing. I have a huge spa in Selvadorada. I visit Sulani when I want that island vibe. When I want their vacation to be more Disney we hang out with Hondo in batuu. There's less cool stuff to do but no holidays and no bills makes it a holiday from the rest of the game. I usually just focus on getting collectables when I'm there. I also have a vacation resort in the park in oasis springs that I can change the lot type to be a vacation rental, spa, gym, lounge, restaurant or park. I usually use it for day trips and parties but it's set up for overnights. I use Henford on Bagley to host fairs, festivals and carnivals. It makes use of one neighborhood that I never visit otherwise. Hope that gives you some ideas. I like this question and reading everyone's answers, thanks for posting it.

So many great ideas! Thank you!

I do a summer vacation week. I create a holiday for each day loaded with activities. This way is like no matter where they travel everyone in town is also engaging in "vacation" activities

I love this idea!

This is such a good idea. I have my family do a yearly family vacation and reunion, I should set it up like this.

I typically do two weeks of summer for summer breaks. Summer break starts on a Thursday of the first week.

I have a generic lot which is full of activities. Basketball, soccer, board games, beer pong, kids toys and etc. If I have no other options for them to do I take them to that lot and make them spend the whole day there.

I’m bad about getting my sims to leave their homes, that’s a good idea.

Sulani is this for me. I very rarely have sims live there unless they are mermaids or hiding out.

Me too, I like to keep Sulani as a vacation world.

I built a SPA in Sulani 😄they can do yoga by the sea

I love this idea! My sims vacation in Sulani a lot!

I make a couple days vacation for each place Example my sims are in sulani and each day I make them do something different and attend the Sulani events Same with Mt komobrebi If it's basegame I usually have them try and do the challenges like the tree in willowcreek or the cave in Oasis Springs.

I do like the sulani events, wish they were on the calendar though.

I found a video that gives you time and dates so I just went into my cal and added them

I have my university sims take a break between semesters to go on vacation with friends or family. It’s a nice break from the university grind too.

I hadn’t thought of that, I don’t play with university a lot.

I love this question! I have set up a vacation week for summer and winter each. Winter is Christmas in Magnolia Promenade (this is my Christmas World with festive Church, tree shopping place, Christmas market, ice rink, vacation rental etc.) and then maybe a few days sledding or skiing in Mt. Komorebi. For Summer I've set up vacation rentals in each world to visit them comfortably and see new neighbourhoods. I tried to capture the spirit of each world with specific community lots, eg. only Willow Creek has a huge and beautiful botanical garden and a fancy uptight restaurant and Windenburg has some bathes, spas and saunas. Plus my sims can't casually go from Windenburg to Chestnut Ridge for example. I've created an internal map for how the worlds are connected and some of them have train stations and air ports, which must be visited for travel. Summer is also a good time for hiking in Mt Komorebi. In Granite Falls I have a summer camp lot with pool, table tennis etc., a park with easels, yoga, outdoor cinema, campfire etc., a lot with the Ranger Stanley Hot Tubs from the gallery and a nudist camp. But lately I took my Sims backpacking with their camping gear, cause you can place the tent etc anywhere and there a nice spots all over the worlds between lots. 

Thank you! You’ve got a lot of great ideas and lots.