what is the {start time} for {London} has {twinned administrative body} as {Berlin} ?
When did London and Berlin first have the same administrative body?
SELECT ?value WHERE { wd:Q84 p:P190 ?s . ?s ps:P190 wd:Q64 . ?s pq:P580 ?value}
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q84> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P190> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q64> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

About the administration of the respective cities, when did London and  Berlin got their first administrative body?