|Season(s)||1 & 4|
|Appearances||Captain America: The Winter Soldier (MCU)|
"The Hub" (mentioned) (AoS)
"Turn, Turn, Turn" (mentioned) (AoS)(AoS)
The Triskelion is the primary headquarters for S.H.I.E.L.D. The facility houses a secret underground facility where three Hellicarriers were created and modified for Project Insight. The facility was taken over by Alexander Pierce, who wanted to use the ships to eliminate the 20 million people that were determined to be threats by HYDRA, which had infiltrated S.H.I.E.L.D with sleeper agents, such as Jasper Sitwell and John Garrett, for years. Before they could be used, however, the Helicarriers were destroyed by Steve Rogers and Natasha Romanoff, causing damage to the Triskelion and bringing the existence of HYDRA and its secrets to light.
In the aftermath of S.H.I.E.L.D's disbandment, the continued use of the Triskelion is unknown.
- Captain America: The Winter Soldier (MCU)
- Agents of S.H.I.E.L.D.