Piper's bobble top hose (just google pipers kilt hose and shop for the best prices and colors) are the longest I have found. I am 6'5" and wear US13+ shoes, and each of the pairs of pipers hose I have are able to be pulled up a couple inches ABOVE my knee cap before being folded down two or three times to form a nice full turnover top at the appropriate distance below my lower knee cap. Most of the House of Cheviot hose that come in solid colors are also very long but not quite as long as the pipers, while the HoC pattern top hose may or may not be long enough depending on your shanks.