Castelion

Overview

Castelion designs, tests, and manufactures low-cost, mass-producible hypersonic strike systems and other military technologies for national security customers requiring rapid, scalable deployment.

Part of the El Segundo ecosystem

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Timeline

1. Aug 2026Funding Roundcastelion.com ↗

   Castelion Raises $1B Series C to Scale Production of Low-Cost Hypersonic WeaponsCastelion, a cutting-edge defense technology company working to restore America's conventional deterrence capability, today announced a $1 billion Series-C fundraise.

2. Sep 2025Funding Roundtechcrunch.com ↗

   Series B; hypersonic strike weapons (ex-SpaceX founders).