Harris and Klebold wrote much about how they would carry out the massacre , but less about why . A journal found in Harris 's bedroom contained almost every detail that the boys planned to follow after 5:00 a.m. on April 20 , 1999 . In journal entries , the pair often wrote about events such as the Oklahoma City bombing , the Waco siege , the Vietnam War and other similar events , including blurbs and notes on how they wished to " outdo " these events , focusing especially on what Timothy McVeigh did in Oklahoma City . They mentioned how they would like to leave a lasting impression on the world with this kind of violence
Oklahoma City bombing
Oklahoma City bombing
Eric Harris and Dylan Klebold