Petersburg, AK, United States

Petersburg, AK: Submarine Cable Landing Point

Petersburg, AK, located in the state of Alaska, United States, serves as a submarine cable landing point on the southeastern coast of Alaska. Two submarine cables land at Petersburg, AK, connecting it to other points along the Alaskan coastline and forming part of the regional intra-state submarine cable network. Both cables link exclusively to other landing points within the United States, making Petersburg, AK a domestic corridor node rather than an intercontinental gateway.

The two cables serving Petersburg, AK — Alaska United Southeast and SEALink — together provide redundant submarine connectivity along the southeastern Alaskan corridor. This pairing of an older and a more recently commissioned cable reflects ongoing investment in submarine infrastructure serving this part of Alaska, with SEALink reaching readiness for service in 2023, some fifteen years after Alaska United Southeast first became operational in 2008.

Cables Landing at Petersburg, AK

Alaska United Southeast (AU-SE) is a submarine cable measuring 626 kilometres in length, which reached readiness for service in 2008. The cable connects landing points entirely within the United States, routing along the southeastern Alaskan coastline. Petersburg, AK is one of the endpoints on this system, which provides intra-US submarine connectivity in the region.

SEALink is a submarine cable measuring 345 kilometres in length, which reached readiness for service in 2023. Like Alaska United Southeast, SEALink connects landing points exclusively within the United States. Its shorter length relative to AU-SE suggests a more localised routing along the Alaskan coast, and its 2023 commissioning makes it the more recently established of the two cables serving Petersburg, AK.

Regional Context

Within the United States submarine cable landscape, Petersburg, AK sits among 160 landing points spread across the country, which collectively host 113 submarine cables. Compared to high-density landing points such as Boca Raton, FL and San Juan, PR — each hosting eight cables — or Hermosa Beach, CA and Kapolei, HI with five cables each, Petersburg, AK's count of two cables places it in the lower tier of US landing points by cable volume. Its connectivity, however, serves a geographically distinct and remote part of the country where submarine cables represent a primary means of telecommunications link.

Network Role

Petersburg, AK functions as a two-cable domestic terminus, participating in the intra-Alaskan submarine cable corridor through both Alaska United Southeast and SEALink. Rather than serving as an intercontinental hub, it plays a role in sustaining connectivity along southeastern Alaska, a region where overland alternatives are limited and submarine cables carry significant communications traffic between communities. The presence of two cables — one commissioned in 2008 and one in 2023 — adds a degree of redundancy to the local network.

Within the broader United States submarine cable graph, Petersburg, AK represents one of many geographically dispersed landing points that ensure domestic submarine connectivity reaches beyond the contiguous lower forty-eight states into Alaska. Its position as a dual-cable landing point in a sparsely connected part of the national network underscores the role that regional intra-state cables play in extending the overall reach of US submarine infrastructure.