The series was not widely broadcast outside the UK in the 1970s, mainly because it did not require additional money from sales abroad to finance its production.  However the Norwegian Broadcasting Corporation showed the series in 1970 and 1982, entitled Romlingane . It was narrated by Ingebrigt Davik , a popular author of children's books. It was shown on Swedish Television in the late 1960s and 1970s, entitled Rymdlarna . The first 13 episodes were also shown on Czechoslovak Television in August 1972, entitled Rámusíci  as a part of the children's evening program slot Večerníček .
The practice of making offerings at (or to) bodies of water appears to be a very ancient one. There is considerable evidence dating from the early Bronze Age that items such as swords, helmets, shields and other pieces of metalwork (along with human beings) were consigned to rivers and bogs in considerable quantities. A number of very fine specimens of Bronze Age and Celtic weaponry and armour have been found at river sites throughout Britain and Europe, as well as considerable metal and human deposits in bogs in Denmark and north Germany. Two partiucular items whose photographs have long graced books on matters Celtic were found in mud in the River Thames during low water - a bronze horned helmet and a bronze shield decorated with inlays and spirals, while within Mercia itself various votive offerings have been found deposited at several points in the River Severn. Most recently, evidence has emerged from the River Trent in Nottinghamshire of deposits of human bones, particularly skulls, in the river during the late Neolithic or early Bronze Age, though there is no real evidence of deliberate human sacrifice.