I'm going on the Spectrum of the Seas in February 2025 too! So excited.
February to March is when schools in China are back in session, so there probably won't be many kids on board. I think there will be people of all ages on the ship, and about 90% will be Chinese.
Generally, Chinese people are friendly, but they do tend to speak a bit loudly. My Chinese friends have told me that it's normal, and there's nothing to worry about. They're just talking that way, not arguing, but it might be something we're not used to as foreigners.
Typically, we Asians don't like sunbathing much, so the sun deck should not be crowded.
However, the weather in Japan in March can be quite unpredictable. This year, it was both as hot as 28°C (82°F) during the day and as cold as 8-9°C (46-48°F) at night. Be sure to bring a jacket or cardigan just in case.
From what I've seen in videos on Chinese social media, the Windjammer on boarding day can be especially crowded, with lines and ropes to manage the crowd in the buffet. I think Royal Caribbean does a great job handling passenger density, though.
Personally, I'll probably eat at Two70 first and then head to the Windjammer after 2 PM when it should be quieter.
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Since I live near Osaka and Kobe and just visited Yokohama last month, here’s some info on the ports:
Osaka and Kobe are two major cities that are very close to each other.
From the Kobe Port Terminal, it's just a 10-15 minute metro train ride to the city center (Sannomiya station).
Check the link for the location on Google Maps: https://maps.app.goo.gl/vS9KEvzWcV8P2JEd6
From downtown Kobe Sannomiya to Osaka (Osaka or Umeda station) it's 30 minutes.
From Osaka station to the city center (Shinsaibashi or Namba station) it's 7 minutes by subway.
From Osaka station to the Osaka Tempozan Cruise Terminal (Osakako Station) it's only 20 minutes.
https://maps.app.goo.gl/VrtWZ3oUGfKpbKM3A
Japanese trains are very punctual and easy to use, with English signage at every station. You can easily explore on your own without relying on shore excursions.
I recommend visiting Osaka Castle, taking a river cruise in Dotombori, or checking out the Osaka Museum of Housing and Living. These are my top three favorite things to do in Osaka.
As for the Yokohama Osanbashi Pier, it's located right in the heart of Yokohama, near Chinatown and Yamashita Park.
https://maps.app.goo.gl/PNsW19d1M9vRe7BG6
From the pier, it's about an 8-10 minute walk to Nihon-Odori Station on the Minato Mirai Line. This subway line goes straight into central Tokyo without any transfers in under an hour
(40 minutes to Shibuya, 42 minutes to Meiji-Jingu (Harajuku), 52 minutes to Higashi-Shinjuku, and 59 minutes to Ikebukuro).
If you have a lot of luggage and don't want to walk, you can take a taxi or Uber to JR Yokohama Station and catch the Ueno-Tokyo Line train into central Tokyo from there.
Hope you have a wonderful trip!