"Men of Harlech" or "The March of the Men of Harlech" (in Welsh: Rhyfelgyrch Gwŷr Harlech) is a song and military march which is traditionally said to describe events during the seven-year siege of Harlech Castle between 1461 and 1468. Commanded by Constable Dafydd ap Ieuan, the garrison held out in what is the longest known siege in the history of the British Isles. "Through Seven Years" is an alternative name for the song.
"Men of Harlech" occupies an important place in Welsh national culture. The song gained international recognition when it was featured prominently in the 1964 film Zulu.