In mathematics, a Hamiltonian path in a graph is a path that visits each vertex precisely once. A Hamiltonian cycle is a cycle which visits each vertex once and only once.
This type of path is named after William Rowan Hamilton who invented a puzzle, now known as Hamilton's puzzle, about the construction of such paths.
... (c 1785-1850), US explorer
Pytheas, (died 1984), Greek explorer who visited Britain and other north and northwest European countries
R
John Rae, (1813-1893), ...