Question: when did the vikings first sail and reach britain
[{'answer': '6 January 793', 'provenance': [{'wikipedia_id': '19333309', 'title': 'Viking expansion', 'start_paragraph_id': 16, 'start_character': 298, 'end_paragraph_id': 16, 'end_character': 311, 'bleu_score': 1.0, 'section': 'Section::::Britain and Ireland.:England.\n'}]}, {'answer': '786 -- 802'}, {'answer': 'During the reign of King Beorhtric of Wessex ( 786 -- 802 )'}, {'provenance': [{'wikipedia_id': '19333309', 'title': 'Viking expansion', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13164189310826322070}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '19333309', 'title': 'Viking expansion', 'start_paragraph_id': 16, 'start_character': 0, 'end_paragraph_id': 16, 'end_character': 763, 'bleu_score': 0.957408925615394, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13164189310826322070}, 'section': 'Section::::Britain and Ireland.:England.\n'}]}, {'provenance': [{'wikipedia_id': '43464740', 'title': 'List of shipwrecks in the 1st millennium', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The list of shipwrecks in the 1st millennium includes some ships sunk, wrecked or otherwise lost between 1 January AD 1 and 31 December AD 1000, of the Julian calendar.\rhighlight sentence(s) containing evidence, not only the answer', 'The list of shipwrecks in the 1st millennium includes some ships sunk, wrecked or otherwise lost between 1 January AD 1 and 31 December AD 1000, of the Julian calendar.']}}]}, {'provenance': [{'wikipedia_id': '19333309', 'title': 'Viking expansion', 'section': 'Section::::Britain and Ireland.:England.\n', 'start_paragraph_id': 16, 'end_paragraph_id': 16, 'meta': {'evidence_span': ['During the reign of King Beorhtric of Wessex (786802) three ships of "Northmen" landed at Portland Bay in Dorset. The local reeve mistook the Vikings for merchants and directed them to the nearby royal estate, but the visitors killed him and his men. The earliest recorded planned Viking raid, on 6 January 793, targeted the monastery on the island of Lindisfarne, off the north-east coast of Northumbria. According to the 12th-century Anglo-Norman chronicler Symeon of Durham, the raiders killed the resident monks or threw them into the sea to drown or carried them away as slavesalong with some of the church treasures. In 875, after enduring eight decades of repeated Viking raids, the monks fled Lindisfarne, carrying the relics of Saint Cuthbert with them.\rhighlight sentence(s) containing evidence, not only the answer', 'During the reign of King Beorhtric of Wessex (786802) three ships of "Northmen" landed at Portland Bay in Dorset. The local reeve mistook the Vikings for merchants and directed them to the nearby royal estate, but the visitors killed him and his men. The earliest recorded planned Viking raid, on 6 January 793,', 'During the reign of King Beorhtric of Wessex (786802) three ships of "Northmen" landed at Portland Bay in Dorset. The local reeve mistook the Vikings for merchants and directed them to the nearby royal estate, but the visitors killed him and his men. The earliest recorded planned Viking raid, on 6 January 793, targeted the monastery on the island of Lindisfarne, off the north-east coast of Northumbri']}}]}, {'provenance': [{'wikipedia_id': '2119964', 'title': 'History of Scandinavia', 'section': 'Section::::Viking Age.\n', 'start_paragraph_id': 37, 'end_paragraph_id': 37, 'meta': {'evidence_span': ['entitled special protection and rights. During the Viking Age, the Vikings (Scandinavian warriors and traders) raided, colonized and explored large parts of Europe, the Middle East, northern Africa, as far west as Newfoundland. The beginning of the Viking Age is commonly given as 793, when Vikings pillaged the important British island monastery of Lindisfarne, and its end is marked by the unsuccessful invasion of England attempted by Harald Hårdråde in 1066 and the Norman conquest. The age of settlement began around 800 AD . The Vikings invaded and', 'entitled special protection and rights. During the Viking Age, the Vikings (Scandinavian warriors and traders) raided, colonized and explored large parts of Europe, the Middle East, northern Africa, as far west as Newfoundland. The beginning of the Viking Age is commonly given as 793, when Vikings pillaged the important British island monastery of Lindisfarne, and its end is marked by the unsuccessful invasion of England attempted by Harald Hårdråde in 1066 and the Norman conquest. The age of settlement began around 800 AD', 'During the Viking Age, the Vikings (Scandinavian warriors and traders) raided, colonized and explored large parts of Europe, the Middle East, northern Africa, as far west as Newfoundland. The beginning of the Viking Age is commonly given as 793, when Vikings pillaged the important British island monastery of Lindisfarne, and its end is marked by the unsuccessful invasion of England attempted by Harald Hårdråde in 1066 and the Norman conquest. The age of settlement began around 800 AD .']}}]}]