  In the present paper, firstly we obtain the general expression of canal
hypersurfaces in Euclidean n-space and deal with canal hypersurfaces in
Euclidean 4-space E4. We compute Gauss map, Gaussian curvature and mean
curvature of canal hypersurfaces in E4 and obtain an important relation between
the mean and Gaussian curvatures as 3Hrho = Krho^3-2. We prove that, the flat
canal hypersurfaces in Euclidean 4-space are only circular hypercylinders or
circular hypercones and minimal canal hypersurfaces are only generalized
catenoids. Also, we state the expression of tubular hypersurfaces in Euclidean
spaces and give some results about Weingarten tubular hypersurfaces in E4.
