The legend is well known of how Hubert was so devoted to the chase that he used to hunt even on the festivals of the Church, and how his conversion was brought about by seeing a stag one Good Friday with a shining cross between its horns. More sober history attributes the change of life which turned the mighty hunter into a priest to the pious counsels of St. Lambert, Bishop of Maestricht, who persuaded him to go on a pilgrimage to Rome, where he finally resolved to devote himself to the cause of religion. He was at Rome when the news came that Lambert had been murdered in revenge for having publicly censured the evil life of Pepin's mistress Alpaïde. On hearing of this tragedy the Pope made Hubert Bishop of Maestricht, and he removed the bishopric to Liége, which grew, under his rule, from a mere village into a large town surrounded by walls built on land given by Charles Martel, afterwards famous as the great champion of Christendom at the Battle of Tours, and son of that Alpaïde who was responsible for the death of Lambert. Municipal laws and courts for the administration of justice were established, and a regular system of government soon followed. Bishop Hubert spent much of his time among the woods and mountains, no longer as a hunter, but as a missionary; and the relics of the patron saint of huntsmen, who died in May, 727, are still preserved in a chapel at the town of St. Hubert, which lies in the midst of a wide forest on the southern tableland of the Ardennes. Liége prospered under the Emperor Charlemagne, who conferred important privileges on the town, and enriched the bishops, who gradually acquired that temporal power which they wielded for so long a time, after the vast empire of Charlemagne had fallen to pieces during the ninth century. The real founder of the temporal power of the bishop princes of the Principality of Liége seems to have been Notger, who was made Bishop by Otho the Great in the year 971. He strengthened the walls of the town, and made it known that law and order must be maintained within the diocese. But the great nobles had their feudal castles, from which they sallied forth to plunder and oppress their weaker neighbours, and close to Liége was the castle of Chèvremont. This stronghold stood on a hill near the site of the modern watering-place of Chaudfontaine, and was surrounded by the cottages of the baron's vassals, and by several chapels and religious houses founded by fugitives who had taken refuge there during the years of the Norman invasion, when Liége, Maestricht, Tongres, and the rich abbeys of Malmedy and Stavelot, had been laid waste.