I noted on the map the existence of this cairn on Bridgeton Hill when last I visited The Cloch stone circle, but that was in late summer, and the field containing the cairn was rampant with vegetation. So I placed it on my to-do list for a fine winter's day. Today was the day, and I renewed the search during a brief stop on my way to enjoy the Auchmithie Clifftop Walk.
Heading south past Johnshaven, take the second road on the right, which serves Mains of Bridgeton and Gateside properties. You can drive up the road, following a gentle S-bend, till it passes between two cottages: here, though the tarmac gives way to a wide, well metalled farm track, continue straight ahead and turn sharp right once past the cottages. Continue till this track dog-legs sharply to the left, and park up. Walk on round the bend for a few metres and you will come to the gate of the field where lies Bridgeton Hill Cairn. All that remains is to follow the field boundary in a northeasterly direction till you are about 20 metres from the end of the field.
Though close to the cairn, which lies slightly uphill, finding it is far from easy as there was no obvious significant rise in the terrain and really nothing much to see at all. But finally, I believe I found the cairn: viewing from uphill, into the low sun, its shadow gave it away. No kerb could be seen but there was one large earthfast stone at its southern margin.
Perhaps others (Drew?) more knowledgeable might like to check this out for accuracy. The GPS coordinates recorded by my camera certainly indicate that I was extremely close to my target.