The _Anglo-Saxon Chronicle_ mentions twenty-four places where the Danes either threw up fortifications (between 787 and 924) or took up quarters either for the winter, or for such a period of time that we may infer that there was some fortification to protect them. The word used for the fortification is generally _geweorc_, a work, or _fæsten_ (in two places only), which has also the general vague meaning of a _fastness_. There are ten places where these works or fastnesses are mentioned in the _Chronicle_:-- 1. NOTTINGHAM.--We have already seen that the Danish host took up their winter quarters here in 868, and that there is the highest probability that the borough which Edward the Elder restored was first built by them. We have also seen that it was a camp of roughly rectangular form, and enclosed a very large area, necessary for great numbers.[119] 2. ROCHESTER.--This city was besieged by the Danes in 885, and they fortified a camp outside. As the artificial mound called Boley Hill is outside the city, most topographers have jumped to the conclusion that this was the Danish camp. But the character of the Danish fortification is clearly indicated in the _Chronicle_: "they made a work around themselves," that is, it was an enclosure.[120] They could hardly have escaped by ship, as they did, if their camp had been above the bridge, which is known to have existed in Saxon times. But Boley Hill is above the bridge. 3. MILTON, in Kent (Middeltune).--Hæsten the Dane landed at the mouth of the Thames with 80 ships, and wrought a _geweorc_ here in 893. Two places in the neighbourhood of Milton have been suggested as the site of it, a square earthwork at Bayford Court, near Sittingbourne, and a very small square enclosure called Castle Rough. Neither of these are large enough to have been of any use to a force which came in 80 ships.[121] Steenstrup has calculated that the average number of men in a Viking ship must have been from 40 to 50; Hæsten therefore must have had at least 3200 men with him. It is therefore probable that the camp at Milton has been swept away. 4. APPLEDORE.--A still larger Danish force, which had been harrying the Carlovingian empire, came in 250 ships, with their horses, in 893, and towed their ships "up the river" (which is now extinct) from Lymne to Appledore, where they wrought a work. There are no earthworks at Appledore now, but at Kenardington, 2 miles off, there are remains of "a roughly defined rectangular work, situated on the north and east of the church, on the slope of the hill towards the marsh, a very likely place for an entrenchment thrown up to defend a fleet of light-draught ships hauled up on the beach."[122] The enclosure was very large, one side which remains being 600 feet long.[123]