In Northern Norway (Nordland and Troms) orcas are visible in the Vestfjorden, Tysfjorden, Ofotfjorden and Andfjorden as the herring gathers in the fjords to stay over the winter and off the Lofoten islands during the summer. At Andenes on Andøya in Vesterålen and around Krøttøya in Troms, sperm whales can be observed year round, summer whale watching trips occur from May till September, winter trips with killer whales and humpback whales are offered from October till April. Tromsø also offers whale watching for sperm and other whales. The continental shelf Eggakanten and deep water where the sperm whales congregate, is very close to shore, beginning only from the Andenes harbour.