Day four brought fine weather and even finer archaeology as we finally began to reveal the Tudor brickwork we've been anticipating.

At the south end of trench 2, on day 1 we had already exposed the corner of the previously excavated brick turret that we found last year.

Today we were finally able to reveal the remaining two sides of the turret that we were unable to get at last year due to the now removed undergrowth, and at the same time we found a new wall springing from the side of the turret and running broadly in the direction of the segment of partly truncated wall that we also found nearby last year (see annotated pic from day 2).

Over the course of the afternoon we removed the overlying demolition rubble to reveal more of this wall, and after a distance of only a little over 2 metres, we found another change in direction which turned out to be yet another polygonal brick turret.

This new turret is broadly the same shape - a kind of truncated octagon - but slightly larger than the other. It isn't completely excavated yet and we don't yet know whether it has a brick floor in the center like its sibling.

The walls of the turret, in common with the other one and the wall connecting them, are quite substantial and top quality Tudor masonry.

Their function is still something of an open question - they both currently appear to be free-standing and not apparently attached directly to any building although this remains to be proved for this new tower - and it is also not yet clear if the connecting wall between them would have been a full-height wall or possibly a threshold of a gateway which the two towers would have flanked. Given the size of the foundations they would presumably have been more than one storey tall, and undoubtedly would have been an imposing and impressive sight as they were approached from the inner courtyard, so whilst this is probably not the gatehouse building itself, it could very well be an outlying structure immediately in front of it.

Meanwhile at the other end of the trench, at a slightly deeper level we finally picked up the line of the truncated wall that we found last year (again, see day 2's annotated pic), the inside of which contains the deep 'cellar' deposit that we are still hunting for in Trench 4.

Initally it seemed as though the line of this wall might correspond to the front edge of the new turret, but after both were properly revealed their alignments seem to be subtly different.

There is now an unexcavated patch between the new turret and this wall which will reveal their relationship hopefully fairly quickly tomorrow.

It was altogether a very good day's work and much needed morale boost after three days of washouts. Hopefully the weather will remain stable enough to keep making good progress but in any event we should have some excellent Tudor archaeology to show the public on Saturday.