BUCHAREST, Romania (AP) - Romania's former royal family put ''Dracula's Castle'' in Transylvania up for sale Monday, hoping to secure a buyer who will respect ''the property and its history,'' a U.S.-based investment company said.

The Bran Castle, perched on a cliff near Brasov in mountainous central Romania, is a top tourist attraction because of its ties to Prince Vlad the Impaler, the warlord whose cruelty inspired Bram Stoker's 1897 novel, ''Dracula.''

Legend has it that Vlad, who earned his nickname because of the way he tortured his enemies, spent one night in the 1400s at the castle.

Bran Castle was built in the 14th century to serve as a fortress to protect against the invading Ottoman Turks. The royal family moved into the castle in the 1920s, living there until the communist regime confiscated it from Princess Ileana in 1948.

After being restored in the late 1980s and following the end of communist rule in Romania, it gained popularity as a tourist attraction known as ''Dracula's Castle.''

In May 2006, the castle was returned to Princess Ileana's son, Archduke Dominic Habsburg.

Habsburg, a 69-year-old New York architect, pledged to keep it open as a museum until 2009 and offered to sell the castle last year to local authorities for $80 million, but the offer was rejected.

On Monday, he put the castle up for sale ''to the right purchaser under the right circumstances,'' said Michael Gardner, chief executive of Baytree Capital, the company representing Habsburg. ''The Habsburgs are not in the business of managing a museum.''

No price was announced, though Gardner predicted the castle would sell for more than $135 million. He added that Habsburg will only sell it to a buyer ''who will treat the property and its history with appropriate respect.''

Habsburg said in a statement: ''Aside from the castle's connection to one of the most famous novels ever written, Bran Castle is steeped in critical events of European history dating from the 14th century to the present.''

According to a contract signed when the castle was returned, the government pays rent to Habsburg to run the castle as a museum for three years, charging admission. After 2009, Habsburg will have full control of the castle, Gardner said.

The government has priority as a buyer if it can match the best offer for the castle, he said.

Opposition lawmakers have claimed the government's decision to return the castle to Habsburg was illegal because of procedural errors.

In recent years, the castle _ complete with occasional glimpses of bats flying around its ramparts at twilight _ has attracted filmmakers looking for a dramatic backdrop for films about Dracula and other horror movies.

Some 450,000 people visit the castle every year, Gardner said.

By ALEXANDRU ALEXE Associated Press Writer

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