The overland run from the Caucasus into Central Asia is one of the last long trips people still plan on paper. It tends to begin in Tbilisi, where the old town climbs the slope below the Narikala walls in tiers of carved wooden verandas. It ends, weeks later, somewhere between the tiled madrasas of Samarkand and the wide avenues of Tashkent. In between sit Yerevan and the Cascade steps, Baku's walled Icherisheher and its Caspian waterfront, the mountain backdrop at Almaty, Ala-Too Square in Bishkek, and the covered trading domes of Bukhara.
The part nobody plans on paper is the phone. Six countries in a row means six separate mobile markets, and the old answer was a kiosk queue in each one: a new number, a new top-up system, a new set of instructions in an alphabet you may not read. Do that six times and it stops being a small errand.
There is a shorter version of the same job. One Horizon regional profile currently reaches Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan and Uzbekistan — the six destinations on the Caucasus and Central Asia eSIM list as it stands now. That turns six phone decisions into one, taken at home before you fly.
Where the arc actually goes
Almost everyone travels this in the same two halves. The western half is a compact triangle: Tbilisi, Yerevan and Baku, close enough that people move between them by night train, shared minibus or a short flight. The eastern half is enormous by comparison — Almaty and Bishkek sit within a few hours of each other, then Tashkent, Samarkand and Bukhara string out west along the old Silk Road, with hours of steppe and desert between them.
Both halves grow detours the moment you have a spare day — the road north from Tbilisi toward Kazbegi, the Black Sea at Batumi, Karakol and Lake Issyk-Kul, the mausoleum town of Turkistan.
The two halves are joined by water and air rather than road. Most travellers fly the gap between Baku and Almaty or Tashkent; a smaller number take the Caspian crossing toward the Kazakh coast. Either way, the arc is not a single drive, and treating it as two linked journeys makes it far easier to plan.
Six markets, one profile
The honest case for a regional plan is not romance about the Silk Road. It is that a phone meeting six national networks needs an answer six times, and settling one answer in advance is less work than settling six on arrival. When at least three of your stops are named on the same live list, the arithmetic usually goes one way:
- A single purchase, made on a laptop at home rather than at a counter in a queue.
- One line to manage in the settings menu, selected the same way at each listed stop.
- Nothing to reinstall at a land crossing — no second QR code, no new account in a script you are still learning.
- One allowance to watch rather than a shelf of leftover balances you never spend.
The counter-case is just as plain. If the trip is really one country with a weekend attached, a single-destination plan is the better instrument; the regional profile earns its place when a route genuinely crosses markets. Either way the catalogue changes over time, so the list attached to the package you actually buy decides things — not the country list in any article, this one included.
The border that changes the route
One fact reshapes the western half more than any other: Armenia and Azerbaijan have no open land crossing between them, so the Yerevan–Baku leg is not a road journey at all. Routes that look like a straight line on a map turn out, on the ground, to double back through Georgia in the middle.
In practice Tbilisi does the work twice. A common shape is Tbilisi to Yerevan and back, then Tbilisi to Baku — or the reverse — with Georgia as the hinge on both swings. It also means the same Georgian ground gets covered twice, which matters when you are deciding how many days a package needs to carry. Visa rules and road conditions shift over time, and they sit outside the connectivity question entirely: verify them from each country's own official channels shortly before you travel.
What the data actually goes on
Long overland travel uses data in short, awkward bursts rather than a steady stream. On this arc it goes on:
- Transport that has to be re-checked — night-train departures out of Tbilisi, minibus stands in Yerevan, the road timetable between Almaty and Bishkek.
- Addresses in three alphabets — Georgian, Armenian and the Cyrillic used across much of the eastern half, pasted into a map or shown to a driver.
- Translation on the spot, at the Green Bazaar in Almaty, the Chorsu Bazaar in Tashkent, or a guesthouse desk in Karakol.
- Photographs going out, from the Registan, from Lake Issyk-Kul, from the Sheki foothills.
- The reassurance message home after a border day, which costs almost nothing and matters more than everything above it.
Tip: On the long legs — a night bus out of Tbilisi, the Almaty–Bishkek road, a train west from Tashkent — the battery usually gives out well before the network does. A phone at three percent is offline wherever it happens to be. Keep the power bank in the bag that stays with you, not the one that goes underneath, and charge in the afternoon rather than at midnight.
Sizing it for weeks, not a weekend
Package sizes on this plan begin at 1 GB and reach 50 GB, over windows of anywhere from 7 to 180 days, so on a trip this long the number of days matters as much as the number of gigabytes. Horizon's own estimate puts seven days of ordinary travel near 3 to 5 GB and a fortnight of multi-country movement nearer 8 to 12 GB; a month-long arc with maps open most days sits some way above that.
Whatever figure you land on, add a margin. Two things push consumption up here that a city break would not: a phone re-scanning for networks at each new market does more background work than one sitting still, and mapping has to be pulled down fresh for each new region rather than once.
Your own number while you move
Dual-line handsets make the tidy version of this easy. Your existing SIM or profile stays exactly where it is, still answering to your own number for voice and messages, while the Horizon line does the data work. Whatever passes over that home line is charged by your own operator on whatever terms your contract sets for use outside your country — worth reading once before departure, not once the statement arrives.
Whether you can pass that data to a second device is a separate question with its own answer. Tethering is governed by the package you bought, the handset and how it is configured, so read the package terms before a working afternoon in Bishkek is built on the assumption.
What to settle before you fly
Set it up at home, unhurried, on a connection you already trust — an evening, not a taxi ride. Keep a copy of the QR image and the confirmation email where they open with no signal at all, and treat both as private, because between them they are the plan. The step-by-step version lives in how to install an eSIM.
Then check compatibility once, properly. A handset locked to a home operator, or too old to take a digital profile, is the one failure no choice of package repairs at the airport.
Reading the trip in two halves
Because the arc really is two journeys, we have written it up that way. The western triangle, the closed border and the day trips that leave each capital are in the South Caucasus guide. The long eastern run — Silk Road cities, big rail legs and the offline habits that make them bearable — is in the Central Asia guide.
If the whole arc is the plan, one profile is the simpler instrument: sort out a Caucasus and Central Asia eSIM in advance, verifying first that every place you mean to visit is named in the live list attached to it. Then spend the journey looking out of the train window rather than down at a settings menu.
