Be aware that this is explicitly discouraged by EFF: Although TrueCrypt hidden volumes may have some practical applications, we think they are unlikely to be u

Be aware that this is explicitly discouraged by EFF: Although TrueCrypt hidden volumes may have some practical applications, we think they are unlikely to be useful in the border search context because they are most helpful when lying to someone about whether there is additional hidden data on a disk. Lying to border agents is not advisable, because it can be a serious crime. [PDF: https://www.eff.org/sites/default/files/filenode/EFF-border-search_0.pdf https://www.eff.org/sites/default/files/filenode/EFF-border-...] PD: Sorry to re-post it here, but I add it, for anyone reading this later. You can get in serious trouble. And to make it worse: If you refuse to provide information or assistance upon request, the border agent may seize your device for further inspection or consider you uncooperative, which the agent may take into consideration when deciding whether to allow you to enter the United States.