See Fig. (???). Schematic view of the far-forward region downstream of ATLAS and various particle trajectories.  Upper panel: FASER is located 480 m downstream of ATLAS along the beam collision axis (dotted line) after the main LHC tunnel curves away.   Lower left panel: High-energy particles produced at the IP in the far-forward direction.  Charged particles are deflected by LHC magnets, and neutral hadrons are absorbed by either the TAS or TAN, but LLPs pass through the LHC infrastructure without interacting. Note the extreme difference in horizontal and vertical scales.   Lower right panel: LLPs may then travel ∼ 480 m further downstream, passing through 10 m of concrete and 90 m of rock, and decay within FASER in TI12.