Sepang was a small town until recent develoipments but it now boasts the Formula One Circuit and the Kuala Lumpur International Airport. You will still though probably want to stay in Kuala Lumpur during your trip to the Malaysian Grand Prix though it is about 45 minutes to drive. Kuala Lumpur though is a great city for those loving either modern cities or cities with a great history.
Formerly the tallest towers in the world the Petrona’s towers are the best known landmark in Kuala Lumpur but the old parts of the city are where you will probably want to spend more of yoru trip with so much to take in. This certianbly should include the fascinating Islamic Arts Museum, and the Sunset Mosque. Though Malaysia is an Islamic country though its culture is very mixed with Hindu, Taoist and Buddhist temples and shrines. The history of the Malay, Indian, Chinese and Indo people all mix here as well making it a really unique place.
For souvenirs and to take in the widest range of sights, smells and atmosphere in one go you should head to the Central Market. What you will also find with a trip to the Malysian Grand Prix combined with a city trip to Kuala Lumper is that it is a city that comes alive at night, once it is cooler and less humid, this is ideal as it allows you to really get the most of your time here alongside a grand prix trip.