Mobile　edge　computing　technology　has　emerged　as　a　novel　computing　paradigm　that　makes　use　of　resources　close　to　the　devices　of　the　smart　rail　system.　Nevertheless,　it　is　difficult　to　support　data　offloading　to　the　stations　directly　from　different　trains　due　to　the　limited　coverage　of　the　stations　equipped　with　MEC　servers.　Therefore,　multi-hop　ad　hoc　network　is　considered　and　introduced　in　this　case.　In　this　paper,　an　improved　architecture　is　proposed　for　the　MEC-based　smart　rail　system　by　blockchain　and　multi-hop　data　communication.　The　requesting　trains　can　offload　the　tasks　to　MEC　servers　by　multi-hop　transmission　between　trains,　even　when　requesting　trains　are　not　covered　by　servers.　Furthermore,　we　utilize　the　blockchain　technology　for　the　authenticity　and　anti-falsification　of　information　during　multi-hop　transmission.　Then,　the　offloading　routing　path　and　offloading　strategy　are　co-optimized　to　minimize　both　delay　and　cost　of　the　system.　The　proposed　majorization　problem　is　formulated　as　a　Markov　decision　process　(MDP)　and　solved　by　deep　reinforcement　learning　(DRL).　In　comparison　to　other　existing　schemes,　simulation　results　demonstrate　that　the　proposed　scheme　can　greatly　improve　system　performance.　©　2023　Linlin　Tian　et　al.