Crow’s Nest (170 seats) is a fore-located observation lounge with panoramic windows, its own bar and large dance floor. The lounge is also used for pre-scheduled events by the Holland America Line's enrichment program, which includes daily dance classes, trivia games, cards playing, karaoke, HAL Cats (8-piece party band) performances, live grand piano performances (in the afternoons and evenings). Crow’s Nest becomes a disco (dance club) at night, with live DJ music and dance contests. During the ship's last refurbishment, the Crow’s Nest bar lounge was renamed "Explorations Central" and its interior was redesigned. The new venue's programming additionally features multimedia series of interactive videos and guides related to the visited destinations part of MS Westerdam's itinerary program. The new Explorations Central (abbrev EXC) provides digital media (videos, ebooks, maps) which passengers can access via Wi-Fi during the current cruise, but also online (before and after the voyage). At the Explorations Central there are also paperback books and paper maps for all the visited by the ship destinations and ports of call.
Explorations Cafe (65 seats patisserie and specialty coffee bar), also serves as the Westerdam ship’s Online Centre (Internet computers room/a partnership with “The New York Times”)
Sliding Dome Cover (retractable glass roof over the Westerdam’s Lido Pool area) with solar panels.
The Loft Lounge (teens-only club for 13-17 yo, open 10am-12pm, with breaks between 12-2pm and 6-8pm; Video Games Arcade, PlayStations, big TVs, Tennis Tables; complimentary supervised youth programming, activities include teen disco, karaoke, movies, sports contests, themed parties)
Club HAL (kids lounge with 2 separate rooms for children 3-7 yo and 8-12 yo, complimentary youth program with supervised age-appropriate activities; open between 9am-11pm with some pauses, depending the Westerdam ship location/at port or at sea; bookings required).
During the 2017 refurbishment, here the sunbathing area (aft of the observation lounge) will be redesigned. The new deck layout of Observation Deck shows cruise cabins from VB10001 to VB10026, in categories VB (Deluxe Verandah) and K-Interior (Large and Standard).