Rockabill

Overview

Rockabill is a short-haul submarine cable system spanning 221 kilometres across the Irish Sea, connecting Ireland and the United Kingdom. It serves the bilateral corridor between these two countries, providing a dedicated link between the Irish and British coastlines.

Route and Landings

In Ireland, the cable lands at Portrane, a coastal location north of Dublin on the Irish Sea shore. In the United Kingdom, the cable comes ashore at Southport, on the northwest coast of England. The two landing points together define the cable's cross-Irish Sea trajectory.

Ownership and Operators

Rockabill is owned solely by euNetworks, a European bandwidth infrastructure company that operates a network of fibre and data centre assets across multiple European countries. As sole owner, euNetworks controls the full capacity and operations of the system.

Status and Timeline

Rockabill entered service in 2019 and is currently operational. The cable represents a relatively recent addition to the Ireland–United Kingdom submarine cable inventory.

Regional Context

The Irish Sea corridor that Rockabill serves is also crossed by EXA North and South, a longer system linking Ireland and the United Kingdom at 12,200 kilometres of total length. In comparison, Rockabill is a short, point-to-point system focused exclusively on the bilateral Ireland–UK segment rather than serving a broader intercontinental route. Other cables with landings in the United Kingdom — including 2Africa, the Europe India Gateway, Atlantic Crossing-1, Apollo, and Glo-1 — serve far longer intercontinental corridors and are not direct counterparts to Rockabill's intra-regional role.

Recent latency measurements across 102 ping tests over the past 60 days show an average round-trip time of 33.7 ms, with a best recorded result of 19.7 ms. These figures reflect the cable's short physical distance across the Irish Sea.

Strategic Role

At 221 kilometres, Rockabill offers a direct and geographically compact submarine connection between Ireland and the United Kingdom. Its Portrane landing point places it in proximity to one of Ireland's established submarine cable hubs, while the Southport terminus provides access to northwestern England. The cable supports bandwidth demand between the two countries through a route that is distinct from the longer, multi-country systems that also touch the UK coastline.