Before the border
Learn how roaming, local SIMs, eSIMs, Wi-Fi, and offline preparation fit together.
Modern startup publication · Issue 01
Connectivity for the in-between
A modern reference desk for choosing mobile access with clarity, context, and fewer assumptions.
Research, comparison, and country notes for Europe
The desk
Useful context for the handoffs.
A phone can be ready at the airport and still feel offline two hours later. The reason may be a plan, a device setting, a network agreement, a tunnel, or a simple expectation mismatch. Passage Index makes those conditions easier to understand.
We compare how travel connectivity works, not which commercial provider should win. Our pages explain the vocabulary, identify questions worth asking, and separate broad regional patterns from details that can change. This is editorial information, not telecom advice or a purchasing funnel.
Read the method
See the criteria used for neutral comparisons: coverage, compatibility, support, speed expectations, and transparency.
Country notes
Use country-level context to plan for cities, rail corridors, rural areas, and crossings.
Connectivity education
Less guesswork, more signal.
What an eSIM actually changes01
Why coverage maps need context02
How to prepare an unlocked device03
What can happen at a border04
How to keep essential access offline05
Editorial note. This suite is openly connected: the same project maintains these ten domain editions. No page presents a fabricated independent publisher, review community, endorsement, or official partnership. Read our standards →