Encyclopedia: Bunker Era

Encyclopedia: The Bunker Era

The Bunker Era is a significant period in the Three-Body timeline, following the deterrence failure and the photoid strike on Trisolaris. Spanning approximately 300 years (2090-2400 AD), its name derives from humanity's response strategy to the threat of Dark Forest strikes — building "bunkers" to shelter from potential cosmic attacks.

After Cheng Xin took over as Swordholder, deterrence collapsed. Trisolaris began invading Earth. Humans were forcibly relocated to Australia, enduring a period of dark rule.

Gravity's democratic vote to broadcast Trisolaris's coordinates exposed both civilizations to the Dark Forest.

Soon, a photoid (near-light-speed mass projectile) struck the Trisolaran home star. Trisolaris was completely destroyed. This was humanity's first time witnessing a Dark Forest strike firsthand.

Since Dark Forest strikes typically destroy stars (exploding a star takes out the entire system), the safest strategy isn't to fortify Earth but to: build space cities in the shadow of major planets, using the planets themselves as "shields" against strikes from a specific direction.

Largest and most advanced bunker cluster

Bunker Era space cities used rotational gravity design, generating artificial gravity through spin. Each city could house millions, simulating Earth's ecology with mountains, water, forests, and urban centers. The largest reached tens of kilometers in diameter.

Breakthroughs in curvature drive research (though legally banned)

Cryogenic hibernation matured as standard for interstellar travel

Controlled fusion became the primary energy source

AI-assisted social management

Earth proclaimed a "nature reserve" with restricted development

Humanity decentralized across four bunker clusters

Emergence of the "Starship Earth" concept — some chose to leave the Solar System

"Golden Field" nostalgia — longing for the pre-threat Earth era

Universal cosmology education — every child learns the Dark Forest law

Collective reflection on the Swordholder — Luo Ji revered, Cheng Xin reviled

Around 2400 AD, the Singer civilization dispatched a dual-vector foil to the Solar System.

The Bunker Project proved futile — the dual-vector foil attacks from a two-dimensional direction, unaffected by planetary shielding. The entire Solar System was compressed from 3D space into a 2D plane. Every bunker, space city, planet — including humanity — became a 2D "painting."

Proved humanity's adaptability and creativity in facing cosmic threats

Also proved that against higher-dimensional attacks, any 3D defense is limited

Bought 300 years for Starship Earth's escape

The Bunker Era is one of the most imaginative settings in Three-Body III. It doesn't depict grand interstellar war scenes — instead, it shows a civilization's coping strategy and social psychology facing "announced destruction."

When you know destruction is inevitable, what do you choose to do? The people of the Bunker Era chose: keep living, keep creating, keep loving. That choice itself is what makes civilization great.