Question: What structure in Venice can be visited that opened its doors in 1424.?
Answer(s):
answer: Doge's Palace

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.07_pf)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.07_pf ns:travel.travel_destination.tourist_attractions ?x .
?x ns:architecture.structure.opened "1424"^^xsd:dateTime . 
}