Arch Intersections is a Geometry Nodes group that computes intersections between curves or vectors. It accepts curves, mesh points, or point clouds with vector attributes as inputs, and generates points, curves, or trimmed curves as outputs. The node group includes features for trimming curves inside or outside, projecting intersections, and supporting cyclic curve nesting. It transfers and linearly interpolates attributes onto new intersection points, and provides several optimization pruning modes including U Sweep, 2D Grid, Grid Sweep, and UV Sweep.