Imagine　in　the　future　that　autonomous　vehicles　coordinated　and　guided　by　signal-free　autonomous　intersections　are　able　to　pass　through　the　intersections　immediately　after　the　vehicles　in　the　conflicting　direction　leave.　Meanwhile,　with　the　coordination　of　the　autonomous　intersections,　autonomous　vehicles　on　any　approaching　lane　are　able　to　turn　onto　any　downstream　lane,　expecting　that　driving　in　such　a　road　system,　autonomous　vehicles　can　reach　their　destinations　without　any　on-road　lane　changes,　and　high　traffic　efficiency　will　be　achieved　as　well　as　great　traffic　safety.　To　draw　the　picture　in　detail,　this　paper　designs　a　signal-free　autonomous　intersection　with　all-direction　turn　lanes　(ADTL)　under　the　environment　of　autonomous　vehicles,　and　proposes　a　conflict-Avoidance-based　approach　to　coordinate　all　approaching　vehicles　in　different　directions.　Communicating　with　the　approaching　autonomous　vehicles　and　utilizing　the　approach,　the　autonomous　ADTL　intersection　is　able　to　coordinate　the　approaching　vehicles　in　all　directions　and　guide　them　to　safely　and　efficiently　pass　through　the　intersection.　Two　simulation　scenarios　are　conducted　in　a　road　network　with　an　isolated　intersection　composed　of　four　three-lane　arms.　One　scenario　validates　the　collision-free　design　of　the　system,　and　the　other　shows　that　the　designed　ADTL　intersection　outperforms　the　conventional　signal　controlled　intersection　in　terms　of　traffic　efficiency,　and　is　potentially　better　than　the　autonomous　intersection　with　specific-direction　turn　lanes.　The　autonomous　ADTL　intersection　can　be　an　important　basis　for　designing　a　future　autonomous　urban　road　traffic　system.　©　2016　IEEE.