Changes

The profile shows the average gradient in each section (the vertical scale is exaggerated), thus on leaving Kidderminster the line initially goes downhill with a gradient of 1 in 112. ‘L’ indicates level. According to the GWR gradient profiles, the steepest gradient on both the orignal Severn Valley Railway and the Loop line did not exceed an average of 1 in 100 in any section. The horizontal scale includes the mileages (see below).

The location of stations, bridges and other structures on the railway network are measured from a datum point (normally a major terminus). For the majority of the railways associated with the SVR the datum point was London Paddington (the exact zero point being the Paddington Suburban Tunnel boundary with the Metropolitan Railway). The individual routes used to reach those locations are identified by [[Engineer's Line References]] (ELRs). Mileage Posts commonly appear at  The maps of the lineside, usually at ¼ mile intervals, to confirm SVR shown below have been annotated with mileages taken from the relevant distancesELRs. All figures are shown in miles and chains (one chain is equal to 22 yards or 1/80th of a mile).

===Mileage PostsMileposts=== Early railway fares were set by distance, therefore it was necessary for railway companies to provide their passengers with a means of determining the distance travelled. The Railways Clauses Consolidation Act 1845 Section 94 stated "''The company shall cause the length of the railway to be measured, and milestones, posts, or other conspicuous objects to be set up and maintained along the whole line thereof, at the distance of one quarter of a mile from each other, with numbers or marks inscribed thereon denoting such distances''.<ref>[http://www.legislation.gov.uk/ukpga/Vict/8-9/20#pb9-l1g104 Railways Clauses Consolidation Act 1845] Retrieved 23 May 2016</ref> Mileage posts Mileposts showing the distance from London Paddington, as measured above, can be seen at the lineside. In the second example shown, the distance just south of Arley Station is 140&frac34; miles (the vertical bars below the number show the number of quarter miles). One mileage post milepost is situated at the foot of Highley Signal Box, showing that it is exactly 143&frac14; miles from Paddington.

The locations of the principal mile posts mileposts were often shown on early Ordnance Survey maps, such as this example from 1903 showing the presence of mileposts (MP) at Kidderminster Junction on both branches of the junction.