<Table> Olympus Mons <Tr> <Td_colspan="2"> Viking 1 orbiter view of Olympus Mons with its summit caldera, escarpment and aureole </Td> </Tr> <Tr> <Th> Coordinates </Th> <Td> 18 ° 39 ′ N 226 ° 12 ′ E ﻿ / ﻿ 18.65 ° N 226.2 ° E ﻿ / 18.65; 226.2 Coordinates: 18 ° 39 ′ N 226 ° 12 ′ E ﻿ / ﻿ 18.65 ° N 226.2 ° E ﻿ / 18.65; 226.2 </Td> </Tr> <Tr> <Th> </Th> <Td> Tallest planetary mountain in the Solar System </Td> </Tr> <Tr> <Th> Peak </Th> <Td> 21,230 m (69,650 ft) above datum 26 km (85,000 ft) local relief 26 km (85,000 ft) above plains </Td> </Tr> <Tr> <Th> Discoverer </Th> <Td> Mariner 9 </Td> </Tr> <Tr> <Th> Eponym </Th> <Td> Latin--Mount Olympus </Td> </Tr> </Table> <Tr> <Td_colspan="2"> Viking 1 orbiter view of Olympus Mons with its summit caldera, escarpment and aureole </Td> </Tr> <Tr> <Th> Coordinates </Th> <Td> 18 ° 39 ′ N 226 ° 12 ′ E ﻿ / ﻿ 18.65 ° N 226.2 ° E ﻿ / 18.65; 226.2 Coordinates: 18 ° 39 ′ N 226 ° 12 ′ E ﻿ / ﻿ 18.65 ° N 226.2 ° E ﻿ / 18.65; 226.2 </Td> </Tr>

The size of olympus mons suggests that the crust of mars is very thick