Did anyone keep the sandals of Jesus that He had worn during His Mission on earth, after His crucifixion ? Is there any Christian group, in any part of the world, that venerates the sandals of Jesus, on the lines of veneration that is given to the Milk Grotto of Bethlehem ?
Most of the sources I've stumbled upon share the same information. Enjoy a direct quote from Mark Rogers' The Esoteric Codex: Magic Objects I:
The sandals are the remains of an ornate fabric shoe (slipper) allegedly from the Merovingian period (fifth to eighth centuries AD), which were given to the Abbey by Rome in the Carolingian period (seventh to ninth centuries). Their political importance has been lost since the Middle Ages but their religious relevance and veracity remains as true as it ever was.
The Sandals of Christ are considered to be among the most notable of the many relics of the church; they are mentioned by King Pepin III (Pepin the short) in the deed of 762, and he is said to have received them from Rome as a gift of Pope Zachary (741-752) and Pope Stephen II (752-757). Pope Zacharias had recognized Pepin's election as king and Pope Stephen II completed the gift in 754. Apart from its religious significance, the relic was the physical embodiment of the Frankish king's legitimation by the church.
Pippin managed the expansion of the small Prüm Abbey over 30 years, leaving it as a huge property named Saint Salvador (Holy Saviour), the favourite monastery of the Carolingian dynasty, which was legitimized by the relic.
The possession of important relics was a means of sustaining church influence and the status of establishments, so in order to compete with a powerful abbey it was important to acquire relics of similar provenance and significance. In the 12th Century the Roman Catholic Diocese of Trier became increasingly powerful and obtained a robe of Christ, called the Seamless robe of Jesus, which was seen as more significant than a pair of sandals attributed to Christ. Over the following four centuries Trier won the power struggle against Prüm and by 1524 had become the major pilgrimage destination. Thus in 1574, Prüm became subordinated to Trier.
Rogers, M. (2014). The Esoteric Codex: Magic Objects I (1st ed.). Lulu.com.