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Blowhole at Bosherston Mere

The photo shows a particularly good example of a blowhole (gloup) at the top of a 35m high headland on the west side of Huntsman's Leap, near St Govan's Chapel.

If high tide coincides with large waves* the blow hole shoots a column of seawater and spray up to 20m above the limestone plateau - people standing to right of blowhole provide scale (*wave buoy NDBC 62303 gave 6.6m wave height on a +6.7mAD high tide at the time this photo was taken).

The noise of the blast of seawater can sometimes be heard in Bosherston Village, 2km away from the blowhole, and the experience is similar to viewing a geyser.

Please note that this is a potentially hazardous location (particularly in stormy weather when sudden gusts of wind could blow you over). Nearby cliff edges are undercut, and the sides of the blowhole or the roof of any unseen cave shaft could collapse.

The feature lies within Range East (part of the MOD's Castlemartin Ranges) and this section of the Pembrokeshire Coast Path is closed when firing is in progress.

For more information about the geomorphology of this area, see Sanctuary Magazine No. 37 (2008), p.12-15
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