At the beginning of July 1579, Tycho wrote letters to Vedel and Dançey announcing that his house was now far enough along to be worth seeing. It was far from complete. Tycho did not move into the house for another eighteen months and was not to pronounce it “finished” until a year after that, in the late fall of 1581. Moreover, he would be adding outbuildings right up to the end of the decade. But with the exterior complete except for ornamentation, the rough framing done inside, and the grounds generally laid out, Uraniborg had assumed enough form to permit Tycho to convey to his friends a good idea of how it would eventually look.

What first greeted the visitor to Uraniborg was Tycho's only concession to the medieval tradition of noble residences as fortified bastions of defense: the wall. Five and a half meters high and nearly five meters thick at its base, this stone-veneered earthen edifice completely enclosed the seventy-eight-meter-square area that constituted the heart of Tycho's island estate. The square was oriented astronomically, with its principal avenue running from the main gate at the east corner (see Figure 4.2) due west to the other portal at D. Through its other diagonal was a north-south path servicing the servants' quarters at the north extremity of the compound (C) and what would become Tycho's printing establishment at the south corner (B).