bù​dào​cháng​chéng​fēi​hǎo​hàn

he who has never been to the Great Wall is not a true man

不到长城非好汉 不到長城非好漢 bù​dào​cháng​chéng​fēi​hǎo​hàn
he who has never been to the Great Wall is not a true man
Literally means one is not a proper person until reaching the Great Wall; used figuratively to mean that one must persist and overcome difficulties to reach a goal