Mariner 4, the first spacecraft to go to Mars (1964 flyby): 228 days
Mariner 6 (1969 flyby): 155 days
Mariner 7 (1969 flyby): 128 days
Mariner 9, the first spacecraft to orbit Mars (1971): 168 days
Viking 1, the first U.S. craft to land on Mars (1975): 304 days
Viking 2 Orbiter/Lander (1975): 333 days
Mars Global Surveyor (1996): 308 days
Mars Pathfinder (1996): 212 days
Mars Odyssey (2001): 200 days
Mars Express Orbiter (2003): 201 days
Mars Reconnaissance Orbiter (2005): 210 days
Mars Science Laboratory (2011): 254 days

www.rayis.me