Systematic siege by trenches
At the siege of Maastricht in June 1673 Sébastien de Vauban applied the method of 'three parallels': three concentric lines of trenches, connected by zigzag approaches, bring the artillery up to the walls of the fortress so that every metre lies under cover from flanking fire. The method turned siege from a chaotic affair with unpredictable losses into an engineering procedure with a schedule and a cost.
Vauban is known on both sides of engineering: he built or rebuilt more than 150 fortresses in France on the sixteenth-century bastion system, and he is the one who worked out the standard way to take such fortresses. Both sides agree in one thing: the seventeenth century made siege a problem that could be calculated in advance.
Why this date
exact: siege of Maastricht, June 1673, under Sébastien de Vauban. The year is confirmed by the list of sieges in the 1911 Britannica.
The quote dates the siege to 1673. The claim 'the parallel method dates from this siege' appears on the same page as a separate sentence without the year: 'The introduction of a systematic approach by parallels ... dates from the siege of Maestricht'. The owner replied (2026-09-26) that a combination of two sentences is not enough; on transfer to core either find a quotation with both the method and the year in one sentence, or re-anchor the node to another event.
Node sources
- Encyclopædia Britannica, 11- (1911), «Vauban, Sébastien le Prestre de», Wikisource Verified 28 Sep 2026
Rheinbergen and Nijmwegen 1672, Maestricht and Trier 1673
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