This study examined the effects of transporting calves less than four weeks of age on a journey at the limit of the maximum time laid down by recent EU legislation. In both summer and winter, 45 calves were transported by road for 19 hours. The journey included a one-hour break on the lorry in which the calves were given either a glucose/electrolyte solution, water, or nothing at all. Control groups of 15 calves remained on farm and were fed normally. The effects of the journey were greater during winter when liveweight loss was greater and more prolonged, and the calves suffered a depression in body temperature. Mid-journey feeding was of minimal benefit. Feeding electrolytes reduced the extent of dehydration as measured by changes in plasma total protein and albumin concentrations, but there was some indication that giving water alone was detrimental. Most of the variables which changed during the journey had recovered in line with the values in the control animals within 24 hours of the end of the journey, but the calves' liveweight and plasma creatine kinase activity took up to seven days to stabilise. The study highlighted the problem that young calves have in maintaining body temperature during transport, especially during colder weather.