Why Croatia Has a Gap in the Middle

I found this gap the way most people probably do: staring at a map of the Croatian coast, tracing the road from Dubrovnik up toward Split, and hitting a small stretch where the country I thought I was driving through simply isn’t Croatia anymore. For about 20 kilometers, the coastline belongs to Bosnia-Herzegovina. Then it’s Croatia again. No peninsula, no strait, no obvious geographic reason — just a country cutting through another country’s coast like a bite taken out of a sandwich.

The town at the center of that bite is Neum, and it deserves its own page rather than a detour here. What I want to get into is the map anomaly itself: why it exists, why it has survived intact through empires, wars, and the breakup of Yugoslavia, and what actually changes now that there’s a bridge that’s supposed to solve it.

An accident of a much older border

The short version is that this isn’t a modern accident at all — it’s a very old, very deliberate one. In 1699, the Republic of Ragusa, the maritime city-state we now call Dubrovnik, was hemmed in by a rising rival: the Republic of Venice, which controlled most of the Dalmatian coast. Ragusa didn’t want a shared land border with Venice, so it negotiated with the Ottoman Empire, which at the time controlled the interior, including what is now Herzegovina. The deal handed a narrow strip of coastline to the Ottomans, creating a buffer zone between Ragusan and Venetian territory. Neither side had to share a fence with the other.

That strip stayed Ottoman, then later became part of Austro-Hungarian and eventually Yugoslav Bosnia-Herzegovina. When Yugoslavia’s internal republics were still just administrative divisions inside one country, none of this mattered much — a truck could roll from Dubrovnik to Split without so much as slowing down at Neum. The republic boundaries were lines on an internal map, not customs posts.

Then came the 1990s. Croatia and Bosnia-Herzegovina became separate, sovereign states, and a three-century-old buffer zone woke up one morning as an international border. The line hadn’t moved. Everything around it had.

What driving the coast actually looks like

If you’ve ever rented a car to drive from Dubrovnik up toward Split, or the other way, you’ve felt this directly, even if you didn’t clock why. The coastal road doesn’t stay in one country. Heading north, you exit Croatia at a Croatian checkpoint, drive a short stretch of Bosnian road through the Neum corridor, then re-enter Croatia at a second checkpoint a few kilometers later. Two passport checks, one short country, all inside what most travelers think of as “driving along the Croatian coast.”

None of this is a formality you can wave past. Bosnia-Herzegovina sits outside both the European Union and the Schengen area, so each crossing is a genuine passport check, sometimes with a short queue behind a coach or two, especially in the middle of summer. I’ve written separately about what this means specifically for the route down toward Mostar, including how many times a given itinerary actually crosses the line — that’s worth reading if you’re heading inland rather than just passing along the coast.

The bridge that fixed one problem

For decades, this double border crossing was simply the price of driving the Dalmatian coast — mildly annoying, occasionally slow, but not really avoidable. That changed in July 2022, when Croatia opened the Pelješac Bridge, a roughly 2.4-kilometer cable-stayed bridge connecting the Pelješac peninsula to the mainland north of Neum.

The point of the bridge wasn’t tourism — it was sovereignty. Croatia had wanted, for years, a way to connect its own southern region around Dubrovnik to the rest of the country without routing traffic through another state’s territory. The bridge, paired with a new bypass highway, does exactly that. Drivers heading between Dubrovnik and Split (or further north) can now stay on Croatian roads the entire way, arcing around Neum rather than through it. No Bosnian checkpoint, no Croatian re-entry, no gap in the passport stamps.

It’s a genuinely useful fix, and I’d recommend it without hesitation to anyone doing a straight run along the coast between Dubrovnik and Split with no reason to stop. Where I’d push back is on the idea, which I’ve seen repeated more than once, that the bridge “solved the border issue” in some general sense. It solved it for through-traffic. That’s a meaningfully narrower claim.

What the bridge doesn’t change

Here’s the part that trips people up when they’re actually planning a trip that includes Mostar. The Pelješac Bridge lets you skip Neum if you’re continuing along the coast. It does nothing for you if your plan is to turn inland at or near Neum and head toward Mostar and the rest of Herzegovina. That route still leaves Croatia and enters Bosnia-Herzegovina in more or less the same place it always did, because the bridge bypasses the corridor rather than replacing the border crossing itself.

I mention this because I’ve had more than one conversation with someone who assumed that, since the bridge exists now, the whole “leaving and re-entering the EU” business was a thing of the past. It isn’t, not for anyone actually going to Mostar. If you’re weighing whether to rent a car and drive yourself, take a long-distance bus, or book a private transfer from the coast, the border crossing is part of the trip either way — the bridge just means fewer people are dealing with it unnecessarily on the parts of the coast that don’t need to touch Bosnia at all.

For what it’s worth, most day-trip operators running tours from the coast into Herzegovina have long since built the border wait into their schedules, which is one reason an organized trip can be less stressful than self-driving if this is your first time crossing. If you’d rather not manage the paperwork yourself, a small-group day trip to Mostar and the Kravice waterfalls from Dubrovnik handles the crossing as part of the itinerary, and the same is true of a day trip to Mostar departing from Makarska further up the coast.

If you’d rather set your own pace and stop where you like, a private day trip to Mostar and Kravice with a driver who already knows the checkpoint routine is worth the extra cost for a lot of travelers.

Why the gap never got closed

It’s fair to ask why, in the twenty-first century, two EU-adjacent countries haven’t just redrawn a line that inconveniences both of them. The honest answer is that neither side has much incentive to. The strip is Bosnia-Herzegovina’s only outlet to the sea — its entire coastline, all 20 kilometers of it, runs through Neum. Giving that up, even in a land swap, would mean giving up the country’s only maritime access. Croatia, for its part, solved its own practical problem with the bridge rather than the border. Everyone got the fix they actually needed without anyone having to give up the thing that mattered to them.

So the gap stays on the map, exactly where the treaty of 1699 put it, and exactly as real at the checkpoint as it’s always been — a reminder, if you needed one on your way down from Split or Dubrovnik to Mostar, that the coast road and the border have never quite agreed on where one country ends and the other begins.

If you’re building out the rest of the trip, the road trip through Herzegovina itinerary and the note on how many days to give Mostar are good next stops, along with a look at what a Dubrovnik day trip to Mostar actually trades off if you’re still deciding between a day trip and staying over.