Meridian trench / Legends The Meridian trench , located on the first Death Star , was a trench encompassing a portion of that battlestation . It housed the station ' s greatest weakness : a thermal exhaust port situated near the station ' s north pole , which is why it was also known as the Polar Trench . If weaponry was fired into it , the exhaust port would cause the Death Star to under go a critical chain reaction . The Alliance to Restore the Republic utilized this trench to destroy the Death Star before it blew up their base on Yavin 4 . Layout . The meridian trench was one of the eighteen narrow canyons that converged on the poles of the Death Star , a moon - shaped deep - space mobile battlestation built by the Galactic Empire . Those large furrows that stretched across the Death Star ' s surface could be easily spotted , even at a distance , and they gave access to multiple docking bays and hangars . The most visible of the trenches ran around the battlemoon ' s equator , separating its northern and southern hemispheres , while the others ran parallel to those . The meridian trench itself was located near the " north pole " of the Death Star . Like the other trenches , the Meridian trench acted as directional markers for Starfighter and shuttle pilots . It was protected to some degree by low - energy shield projectors in terms of entry points as well as disposal ports . The trench overall was wide enough to accommodate three single - pilot starfighters in attack formation . The trench itself ' s height was the equivalent of at least three sub - surface levels . In addition , it contained energy flush vents as well as communications array within the trench , and heat sinks , communications arrays , power distribution nodes , service access ports , shuttle landing pads , cosmic ray sinks , sensor suite fields , defense - field generators , as well as various shield projection towers on the surfaces near the trench . Like all the other trenches , it proved treacherous to even the most skilled starfighter pilots , as it was fitted with many XX - 9 heavy turbolaser towers ( which acted as the primary source for protection ) , several even being on the floor of the trench in addition to just outside of it , and thus left little room for evasive maneuvers . The defensive systems were also programmed in such a way to avoid the turbolaser batteries from either accidentally blasting each other or otherwise damaging the station ' s hull and surface structures . While the Death Star had been designed to withstand massive assaults by a full enemy starfleet , a successful attack by small fighters had never been anticipated during conception . Therefore , the meridian trench granted access to the station ' s major weakness , the thermal exhaust port . Despite this , however , it nonetheless was equipped with a field generator that caused various sensors save for sight to be negatively affected , and generated a distortion field potent enough to cause even enemy starfighters ' maneuverability to be negatively effected to the extent of decreasing to point three . In addition , although the designers for the Death Star had anticipated the possibility that the trenches would be accessible to enemy Starfighters , they were confident that Imperial firepower would readily defeat the threat , and would not cause significant damage , and also included ray - shield projectors around the area of the thermal exhaust port specifically to ensure that it could not be set off by laser bombardment . History . In 0 BBY , the Alliance to Restore the Republic planned on destroying the Death Star over the gas giant Yavin Prime . The plan depended on the ability of a single T - 65 X - wing starfighter to navigate the meridian trench while avoiding the Imperial TIE fighters and the turbolaser towers , and fire two proton torpedoes into the vent reactor core . With the aid of the Force and the timely intervention of Han Solo , the young Tatooinian farmboy Luke Skywalker accomplished the mission . His torpedoes traveled into the reactor core , starting a chain reaction that blew up the battlestation . Behind the scenes . The Death Star ' s meridian trench first appeared in , the first installment of the " Star Wars " original trilogy . For the final dogfight of the movie , Industrial Light & Magic used a puzzle of patterned pieces fitted together on larges tables . In the process , a three feet deep model of the meridian trench and a full - scale thermal exhaust port were also completed . Originally , the meridian trench was intended to get denser and more detailed toward the station ' s poles . This shows in the conceptual drawings by Joe Johnston appearing in the early reference book " The Star Wars Sketchbook " . This was to some extent retained in " Star Wars : The Arcade Game " , as well as the Trench Run sequences in the " Rogue Squadron " series , in order to make the level more challenging .