Highest Library

JW Mariott Hotel; Shanghai, China; 2004.

The library on the 60th floor of the JW Marriott Hotel at Tomorrow Square in Shanghai, China, is situated at 230.9 m (757 ft 6 in) above street level. Membership is available to members of the public and the 103 shelves in the library contains an ever-expanding collection of Chinese and English books. The library measures 57 m² (614 ft²). To walk to the library from the lobby would entail climbing around 1,435 steps.

Source: Guinness World Records 2007

Highest Commercial Decelerator Descent

Macau Tower Sky Jump; Macau, Macau; August 17, 2005.

The highest commercial decelerator descent facility is Sky Jump at Macau Tower Convention and Entertainment Center. The descent starts from level 61 of the tower at a height of 233 m (764.4 ft) from ground level and each descent takes 17-20 seconds to complete. The inaugural jump was completed by A J Hackett (New Zealand) on August 17, 2005.

Source: Guinness World Records 2007

Highest Concrete Dam

Grande Dixence; River Dixence, Switzerland; 1961.

Grande Dixence, on the river Dixence in Switzerland, is the highest concrete dam in the world. It was built between 1953 and 1961 to a height of 285 m (935 ft), with a crest length of 700 m (2,297 ft), using 5,960,000 m³ (7,800,000 yd³, 210,400,000 ft³) of concrete.

Source: Guinness World Records 2007

Deepest Underwater Postbox

Heinz Piorkowski; Wakayama-Ken, Japan; April 23, 1999.

The world's deepest underwater postbox is located 10 metres (32.8 ft.) beneath the waters of Susami Bay, Japan.

Source: Guinness World Records 2007