Booking in advance

You really need to tell us what cities you plan to visit, and when.

Thanks for adding the requested info, Enryu.

It depends on how picky you are about your lodging, and how tight your budget is. If you’re flexible, you’ll find someplace to stay, it just might not be the cheapest option since you’re traveling in peak season.

I wouldn’t travel anywhere in July and August without booking. You can be more flexible in June, but Croatian schools and universities start their long summer holidays in mid June I recall, so places will get busier then.

I'm fussy about accommodations and I try to get the best possible rates - as a solo traveler, lodging is my single biggest expense. So I do a lot of research on rooms and book well in advance, but I make sure that every booking can be cancelled without penalty, usually with 1-3 days notice, but sometimes as much as a week. If it's not, then I don't book it. A very few times, I've had to book rooms in the middle of a trip; then I regret the time I have to spend on it and the stress it causes me. OTOH my trips to Europe are never more than 3.5 weeks. It sounds like you're planning a 2-3 month trip.

As a side note, I see that you are planning to be in Spain in July. That's low season there (except Barcelona) - because of the extreme heat, so it shouldn't be a problem to get rooms more or less at the last minute. However, you might want to change your itinerary to avoid the heat.

Listen to Chani about the heat in Spain from Madrid south. I don't know that you can count on air conditioning in hostels, and that would be 100% essential at that time of year. I spent part of summer 2015 in Sicily and Puglia--areas not as hot as southern Spain, and the heat was really draining. It's one thing on a short trip, but yours is not short.

Plitvice Lakes National Park is a really lovely place, but as of 2015 (pre-COVID) it was unbelievably crowded during day-tripping hours. The walkways were packed. It was not nearly the same experience I had had on earlier trips (a long time ago, before so many people discovered Croatia). The way to avoid that problem is to spend the night near or inside the park, seeing it later in the afternoon on your arrival day and/or first thing in the morning the next day. The hotels in the park are expensive, as you might imagine, and not special at all. You'll need to work a bit to find a place outside the park that's either within safe walking distance (rural roads; probably no sidewalks) or offers shuttle service to the park. You may find some possibilities listed on booking.com or by Googling. You definitely cannot just show up in the area around the park in June or July and expect to find a place to sleep that night. Incidentally there is bus service to the park from both Zagreb and Split.

Croatia has a culture of rented rooms in people's homes that pre-dates Airbnb. the rooms are called "sobe" (plural). You might see signs; if not, some local travel agencies maintain lists of rooms and will book one for you. But counting on finding something the day you arrive in a high-demand location in the summer is really risky if you're on a budget.

Well, I can book in a hotel in southern spain. There area a lot of under $80 per night in southern Spain. Also I'm going to bring Hydro Flask every time I'm going to explore the city or day trip to some place.

In My Croatia trip, Yes, I'm planning to stay overnight in plitvice. I'm going to rent a car in Split. Then early morning of next day I'm going to Plitvice.

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