2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/223623I present a class of objects called gravitational strings (GS) for their similarity to the conventional cosmic strings: even though the former are just singularities in flat spacetime, both varieties are equally "realistic", they may play equally important cosmological rôle and their lensing properties are akin. I argue that the enigmatic object CSL-1 is an evidence in favor of the existence of GS.The published version. Minor correctionsGeneral Relativity and Quantum CosmologyAstrophysicstext