The largest impact crater of the Solar System is:
Valles Marineris
Caloris
Rupos Altai
Aristarchus
Caloris Planitia is a plain within a large impact basin on Mercury, informally named Caloris, about 1,550 km in diameter. It is one of the largest impact basins in the Solar System.  The crater, discovered in 1974, is surrounded by a ring of mountains approximately 2 km (1.2 mi) tall.   
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Valles Marineris
Caloris
Rupos Altai
Aristarchus
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