Baltica: A Baltic Sea Submarine Cable
The Baltica submarine cable connects Denmark, Poland, and Sweden, spanning 437 kilometers across the Baltic Sea. Operational since 1997 (according to GeoCables records), it is owned by a consortium of telecom operators including Arelion, Orange Polska, Slovak Telekom, TDC Group, Telenor, and Ukrtelecom. Baltica serves as a critical link for regional connectivity, facilitating data exchange between Northern and Central Europe.
While Baltica's exact design capacity, fiber pair count, and supplier details are not publicly disclosed, its strategic positioning and multi-operator ownership highlight its importance in the region's telecommunications infrastructure. The cable's latency performance and redundancy options, as well as its historical context, offer insights into its operational role and reliability.
Quick facts
| Cable name | Baltica |
| Length | 437 km |
| Ready-for-service year | 1997 (GeoCables database value; conflicting industry sources, if any, are discussed below) |
| Owners | Arelion, Orange Polska, Slovak Telekom, TDC Group, Telenor, Ukrtelecom |
| Status | In service |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Technology | Not disclosed |
| Landing points | Gedser (Denmark), Kołobrzeg (Poland), Pedersker (Denmark), Ystad (Sweden) |
Route
Baltica connects four landing points: Gedser and Pedersker in Denmark, Kołobrzeg in Poland, and Ystad in Sweden. Gedser, located at the southern tip of Denmark's Falster island, serves as a hub for multiple submarine cables, including Elektra-GlobalConnect 1,
Germany-Denmark 3, and
GlobalConnect-KPN. Kołobrzeg, a coastal city in Poland, is a significant Baltic port, while Pedersker and Ystad are situated on the Danish island of Bornholm and the Swedish mainland, respectively. This route facilitates regional connectivity across the Baltic Sea, linking Scandinavia with Central Europe.
Why it was built and what it carries
Baltica was constructed to enhance cross-border telecommunications in the Baltic region, providing a reliable and direct link between Denmark, Poland, and Sweden. Its multi-operator ownership suggests a shared interest in regional connectivity and capacity sharing. While specific details about its data traffic or bandwidth utilization are not publicly disclosed, the cable likely supports internet, voice, and data services for both residential and enterprise customers.
History: what can be established
GeoCables records indicate that Baltica became ready for service in 1997. If alternative industry sources suggest a different year, such discrepancies could arise from variations in documentation practices, delays in commissioning, or differences in defining "ready for service." However, no conflicting dates are explicitly noted in the available data, leaving 1997 as the most reliable reference for its operational start.
Capacity and technology
Publicly available information does not specify Baltica's design capacity, fiber pair count, or the technology used in its construction. Without operator documentation, attributing these characteristics would be speculative. Given its 1997 commissioning date, the cable likely employs optical fiber technology typical of that era, but any upgrades since then remain unverified.
Latency: the physics
The calculated one-way light propagation latency for Baltica's 437 km wet segment is approximately 2.1 milliseconds, with a theoretical round-trip time (RTT) floor of 4.3 milliseconds. Real-world latency measurements are higher due to additional factors such as land-based network routing and terminal equipment processing.
Live measurements from remote probes provide mixed insights. For example, Gedser to Kołobrzeg shows an average RTT of 12.8 milliseconds, but the minimum recorded value of 1.7 milliseconds is below the physical floor of 4.3 milliseconds and is thus a measurement artifact, likely caused by rate-limited ICMP replies from intermediate routers. Other measurements, such as Moscow to Pedersker (31.7 milliseconds) and Kyiv to Pedersker (36.4 milliseconds), reflect the full internet path and include latency contributions from terrestrial networks.
Redundancy: what happens if it breaks
Baltica's corridor is supported by alternative cables at Gedser, including Elektra-GlobalConnect 1, Germany-Denmark 3, and GlobalConnect-KPN. These cables provide potential redundancy in case of outages or maintenance on Baltica. Submarine cable repairs typically involve deploying specialized vessels to locate and fix faults, a process that can take days or weeks depending on weather conditions, fault location, and cable accessibility.
Bottom line
- Baltica spans 437 km, connecting Denmark, Poland, and Sweden.
- Operational since 1997, according to GeoCables records.
- Owned by Arelion, Orange Polska, Slovak Telekom, TDC Group, Telenor, and Ukrtelecom.
- Design capacity, fiber pairs, supplier, and technology are not publicly disclosed.
- Theoretical RTT floor for the wet segment is 4.3 milliseconds; live latency measurements reflect the full internet path.
- Redundancy options exist via other cables landing at Gedser.