Prague: You'll find excellent 4G and 5G coverage across the capital, including major tourist areas like the Old Town Square, Charles Bridge, and Prague Castle. The Prague Metro (Pražské metro) has reliable signal on most station platforms and increasingly within the connecting tunnels, though brief drops between stops can occur on older lines. Indoor reception is strong, but can weaken inside deep cellars or buildings with very thick stone walls.

Brno: As the Czech Republic's second city, Brno boasts comprehensive 4G and expanding 5G networks. Connectivity is dependable in the city center, around the Špilberk Castle, and in its many university districts. Public transport, like trams and buses, has uninterrupted service as it is all above ground. Indoor coverage in modern buildings is great, though some older, historic structures may have weaker signal penetration.

Ostrava: This major city in the Moravian-Silesian region has strong and reliable 4G/LTE coverage from all main operators. Signal is particularly robust in the central districts and regenerated cultural sites like the Dolní Vítkovice industrial complex. 5G is steadily being rolled out, ensuring fast data speeds throughout the urban area.

Pilsen: Famed for its brewery, Pilsen offers excellent mobile connectivity. You can expect a strong, stable signal in the historic Republic Square, the Pilsner Urquell Brewery tour areas, and throughout the city's residential neighborhoods. Coverage is consistent, with few dead spots in the main urban zones.

Český Krumlov: Despite its medieval layout and UNESCO World Heritage status, this popular tourist town has very good 4G coverage in its main areas, including the castle complex and along the Vltava river. The signal can be less reliable deep inside the thick-walled historic guesthouses, restaurants, or down in the castle cellars- a common quirk in such a well-preserved town.

Dálnice (Motorways): Major motorways like the D1 (Prague-Brno-Ostrava), D5 (Prague-Plzeň-Germany), and D8 (Prague-Germany) have excellent and consistent 4G/5G coverage from all main providers. You may experience very brief signal drops in some deep cuttings or highly rural segments, but connectivity is generally reliable for navigation and streaming.

Main Rail Corridors: Travel on primary train routes, such as those connecting Prague to Brno, Ostrava, or Plzeň, offers good connectivity. Modern high-speed trains (Pendolino, Railjet) often have on-board Wi-Fi, but the direct cellular signal can be intermittent in deep valleys, forested areas, and tunnels between major cities.

Mountain Ranges: In mountainous border regions like the Krkonoše (Giant Mountains) in the north or Šumava (Bohemian Forest) in the south, mobile signal becomes unreliable. While towns and ski resorts are well-covered, expect significant dead zones on hiking trails and in remote forested areas away from civilization.

Road and Rail Tunnels: Expect a temporary loss of mobile signal when passing through longer tunnels. This is common on motorways like the D8 approaching the German border and on modernized railway lines. Your connection will restore automatically as soon as you exit the tunnel.

Rural and Borderland Areas: Sparsely populated regions, particularly along the borders with Austria and Germany in South Bohemia or near the Jeseníky mountains, often have weaker or patchier coverage between towns and villages. Maintaining a constant high-speed connection in these remote areas can be challenging.