Sharon's railway sleeper garden wall with RSJ steel beams

They are certainly reclaimed old railway sleepers. Not only due to the weathering and the colour, but also due to the dimples or indentations where the weight of the train and track has pressed the railway sleeper onto the ballast underneath, and made marks. The cracks are part of the natural seasoning of the timbers that probably occurred about 40-50 years ago, and shouldn’t really change. Sometimes the railway sleepers can swell or contract in wet or hot weather, which can effect the opening or closing of any cracks, but shouldn’t change the strength or solidity of the railway sleepers. In terms of maintenance, most people leave them as they are to naturally weather, however you can apply some kind of fence or shed preserver, if you want to smarten them up or change the colour. The look of any landscaping project is inevitably subjective, but in my mind your railway sleepers look very effective as weathered, sturdy and industrial timbers. But there again I’m biased!