# Canonical recap data for Telegraph Line Opens London-Paris (1851)
# Source: https://recap.at/1851/telegraph-london-paris
# Format: YAML 1.2 (UTF-8). Generated at request time.
slug: telegraph-london-paris
canonicalUrl: "https://recap.at/1851/telegraph-london-paris"
title: Telegraph Line Opens London-Paris
aliases:
- London-Paris submarine cable
- First cross-Channel telegraph
- 1851 submarine telegraph
subtitle: The first submarine telegraph cable connecting Britain and France inaugurated instantaneous long-distance communication across international borders.
recapType: global_event
eventStatus: concluded
startDate: 1851-01-01
datePrecision: year
year: 1851
decade: 1850
country:
name: United Kingdom
slug: united-kingdom
summaryShort: Electrical telegraphy is point-to-point distance communicating via sending electric signals over wire, a system primarily used from the 1840s until the late 20th century. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were de
summaryLong: Electrical telegraphy is point-to-point distance communicating via sending electric signals over wire, a system primarily used from the 1840s until the late 20th century. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were devised to send text messages more quickly than physically carrying them. Electrical telegraphy can be considered the first example of electrical engineering.
lede: On August 13, 1851, the first submarine telegraph cable connecting London and Paris went live, allowing messages to cross the English Channel in seconds for the first time. The 21-mile cable, laid by the British and French governments, reduced communication between the two capitals from hours by courier to near-instant electrical transmission. It proved submarine telegraphy was viable and sparked a global race to wire the world.
heroImageUrl: "https://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Cooke_and_Wheatstone_electric_telegraph.jpg/1280px-Cooke_and_Wheatstone_electric_telegraph.jpg"
heroImageCredit: Wikipedia · "Electrical telegraph"
importance: 87
sourceConfidence: 75
keyFacts:
- label: Cable length
  value: 21 miles across the English Channel
- label: Launch date
  value: August 13, 1851
- label: Message transmission time
  value: Near-instantaneous (vs. hours by courier)
- label: Countries involved
  value: United Kingdom and France
- label: Cable depth
  value: Maximum 300 feet below sea level
timeline:
- date: 1844-01-01
  title: Telegraph established in Britain
  description: Samuel Morse's telegraph system becomes operational in the United States; British engineers begin adapting the technology.
- date: 1848-01-01
  title: Submarine cable experiments begin
  description: William O'Shaughnessy and others conduct early trials with insulated cables submerged in water to test signal transmission.
- date: 1851-08-13
  title: London-Paris cable goes live
  description: The 21-mile submarine telegraph cable across the English Channel successfully transmits its first messages between London and Paris.
- date: 1858-07-27
  title: Transatlantic cable operational
  description: The first successful transatlantic telegraph cable links Valentia Island in Ireland to Newfoundland, enabling London-New York communication.
- date: 1870-01-01
  title: Global submarine cable network accelerates
  description: Multiple submarine cables connect Europe to Asia, Africa, and Australia, establishing the foundation for worldwide telegraphy.
sources:
- url: "https://en.wikipedia.org/wiki/Electrical_telegraph"
  title: Telegraph line
  provider: Wikipedia
related: []
impactStatement: The successful crossing of the English Channel by telegraph cable demonstrated that electrical communication could operate reliably underwater over significant distances. This vindication of submarine cable technology unlocked decades of international infrastructure investment, eventually enabling global communication networks that reshaped commerce, diplomacy, and news distribution.
categories:
- tech-launch
taxonomy:
domain: technological
eventTypes:
- tech_launch
- infrastructure_rollout
canonicalClasses:
- creation
- transformation
impactRadius: global
velocity: gradual
predictability: forecastable
intentionality: planned
domainCoupling: multi_domain
lifecycleClass: birth
metaDescription: "August 1851: First submarine telegraph cable links London and Paris, proving underwater electrical communication works."
wikidataQid: Q6501061
archiveSnapshots:
- url: "https://web.archive.org/web/20260609201916/https://en.wikipedia.org/wiki/Electrical_telegraph"
  capturedAt: 2026-06-09
  label: Telegraph line
  originalUrl: "https://en.wikipedia.org/wiki/Electrical_telegraph"
