That's Suzutsuki's mostly scrapped and concrete filled hulk behind her in the top pic, apparently Fuyutsuki is also there but buried under the parking lot, hence her being near fully buried here.
They're both underground. The destroyer with the hull partially visible is the older Momo-class destroyer Yanagi.
Why··Even after defeating the boss (Entombed Anti-Air Guardian Winter Princess), Ofuyusan doesn't grow back...OfuyusanOfuyusan...do you hate me?At the Kitakyushu warship breakwater after the winter event.I'm here。Kasumi-san, can you lend me a hand?What are you doing waiting for an excavator?But, I thought it would be faster to meet her in human form if I dug up her "real hull"!Suzu, the one underneath there is you.Stop it! The boss is coming back!