Sites

(UK) University of Wales, Bangor (Popularity: )
http://www.informatics.bangor.ac.uk/public/mathematics/research/cathom/cathom1.html
School of Informatics, Category Theory and Homotopy Theory.

(UK) University of Wales, Bangor (Popularity: )
http://www.informatics.bangor.ac.uk/public/mathematics/research/algtop/algtop2.html
School of Informatics, Algebra and Algebraic Topology.

(UK) University of Manchester (Popularity: )
http://www.maths.man.ac.uk/DeptWeb/Groups/Pure/Topology.html
Topology, Geometry and Combinatorics Group.

(Belgium) K.U. Leuven, Kortrijk Campus (Popularity: )
http://www.kulak.ac.be/facult/wet/wiskunde/algtop/
Algebra and Topology Research Group.

(USA) Auburn University. (Popularity: )
http://topo.math.auburn.edu/
Topology and its Neighborhood.

(UK) University of Oxford (Popularity: )
http://www.maths.ox.ac.uk/topology/
Topology group. People, events, preprints, links.

(UK) University of Liverpool (Popularity: )
http://www.liv.ac.uk/~su14/knotgroup.html
Knot Theory Research Group.