Most visa lookups end in a tidy answer: visa-free, visa on arrival, e-visa, or apply at the consulate. But for a handful of country pairs the honest answer is different. Sometimes the shared border is closed and the two governments have no relations, so there is no visa to apply for at all. Other times travel is perfectly possible — but only through a special permit system that is not the ordinary passport visa other nationalities use. Getting this right matters: telling someone to “apply for a tourist visa” for a trip that doesn’t work that way is worse than unhelpful.
Closed border: Armenia and Azerbaijan
Armenia and Azerbaijan have had no diplomatic relations and a closed land border since the conflict of the early 1990s. There are no direct flights, no open crossings and no consular services between them. In practice this means ordinary travel is not possible in either direction — and any visa-free or e-visa entitlement that looks valid on paper does not reflect a usable route.
- Azerbaijan does not admit holders of Armenian passports, and in practice also refuses entry to people of Armenian descent regardless of which passport they carry.
- Azerbaijan separately bars — and may prosecute — any traveller of any nationality who has visited the Nagorno-Karabakh region without Azerbaijani authorisation. An itinerary that includes that region can cost you entry later.
- A peace-treaty framework between the two countries was initialled in 2025, so this could ease over time. Because it is volatile, we date it and re-check it rather than treating it as permanent.
On our site these pairs no longer read as “apply for a visa”. The Armenia → Azerbaijan page and the reverse Azerbaijan → Armenia page both show a sourced “travel not permitted” explanation, and the Armenian passport overview lists Azerbaijan under “Travel Not Permitted” rather than burying it in a visa-required column.
Permit-only, not a passport visa: Taiwan and mainland China
Travel between Taiwan and mainland China is entirely possible — but it does not run on the ordinary passport visa that other nationalities use. Instead each side has its own permit system, and the document, not a tourist visa sticker, is what gets you across.
- Residents of Taiwan travelling to the mainland use the Mainland Travel Permit for Taiwan Residents (台胞證, the “Taiwan Compatriot” permit), issued by the mainland authorities as a multi-year card or an electronic permit — not an ordinary Chinese L, M or Z visa.
- Residents of mainland China travelling to Taiwan need an Exit & Entry Permit issued by Taiwan’s National Immigration Agency, granted under specific categories such as business, professional exchange, family visit or study, plus the relevant mainland exit endorsement.
- Independent (individual) tourist travel from the mainland to Taiwan has been suspended since 2019; group and category-based travel continues when permitted. These rules shift with cross-strait relations, so confirm the current scheme before booking.
We show this as a sourced advisory above the visa details rather than erasing them: the Taiwan → mainland China page and the mainland China → Taiwan page both explain the permit system and note that the ordinary visa is not the route used. The Taiwanese passport overview flags China with the same note.
Three patterns to recognise
- No diplomatic relations / closed border: there is no visa to issue and no admission (Armenia↔Azerbaijan; and, covered separately, Israel and several states).
- Special permit required: travel is possible, but through a permit scheme rather than the ordinary passport visa (Taiwan↔mainland China).
- Prior-travel sensitivity: where you have already been can bar a later entry (a Nagorno-Karabakh visit for Azerbaijan; an Israeli stamp for some states).
How we keep this honest
Before any visa fields are shown, each page resolves the country-to-country relationship. Where entry is not permitted, the page shows a sourced explanation instead of an “apply” button and never publishes structured data implying a visa is available. Where travel runs on a special permit, we say so plainly and keep the details in context. Every restriction carries a source and the date we last verified it — and because borders reopen and permits change, we re-check the volatile ones. For the relationship side of this work, see our companion piece on which passports can’t travel to Israel.