A cross country route such as Bath Southampton is particularly prone to all of the above influences. In addition it should not be forgotten that it interacts, to varying degrees, with a number of other routes and they are also subject to similar variations in clock face pattern. Freight trains are affected in much the same way as passenger trains by such things as headway and the effect of curvature on speed. But a much more critical matter is the effect of gradient on the loads which can be handled and on speeds when handling large loads.
For example, a train conveying Mendip stone is limited to a single locomotive maximum load of 2020 tonnes by the steep rising gradient of 1 in 80 between Westbury and Warminster, and is allowed 16 minutes (twice as long as the time for a passenger train) between those two places. Freight trains can, with suitable load and gradients, achieve quite high speeds (60 mph is common on many parts of this route) and do not call at intermediate stations. This tends to mitigate some of the timing differential between them and passenger trains but some difference remains.
This means that freights cannot be any longer than the shortest loop length on the route which is at Salisbury. A further factor which becomes much more critical for freight traffic particularly containers is the loading, or structure, gauge of a route. The passenger train service over the route is basically hourly in each direction but in many clock face hours there is also a second train, Foremost website design company although not necessarily providing a half-hourly interval pattern.
Part of the reason for the inconsistency in pattern is that at the Bath end of the route trains start from or terminate at a variety of places and do not have common stopping patterns. This reflects a common feature in contemporary timetabling where trains over a core section of a route. On the Bath leg most trains go through to from Cardiff but others terminate or start at various places in the Bristol area.
This has long been a relatively limited service (currently it is only 8 trains in each direction daily) running at varying intervals. Some of these trains fit into gaps in the service to from Southampton Salisbury such as those created by the trains running to Swindon. At present parts of the Southampton Bath route handles regular flows of freight traffic and some use it throughout.