Posted September 21st, 2017, 05:43 PM
Date? Evening are slow in Victoria, but if it's next summer you might be able to visit the excellent Royal BC Museum which stays open late some nights in high season.
If it's the tail end of this year, then touristy shops downtown will also stay open late for cruise ships but most of the sites remain with a closing time of pretty early (6pm or even earlier). Some are quite seasonal - e.g. Butchart Gardens, which is open until 10pm in summer but as early as 5pm offseason, so you may or may not be able to get here independently (with 6 hours, you could do it by yourself without too much risk if they're open late enough for you to get there before closing to new entries - you get at least an hour after that inside). Cruiseline excursions to here go later than official hours, at a very marked up price, but it may be the only possible way to see the gardens depending on date.
Horse & Carriage rides could be enticing to the wee one and will be available - NB: don't book a cruiseline version or any mention of Trolley as this is a big trailer with bench seats and less than half of them have any kind of view.
Otherwise, just walking around downtown is nice - it's very British, lots of lit-up buildings after dark, there are usually buskers performing in the inner harbour close to the Empress hotel (which serves a hugely pricey Afternoon tea, with late seating for cruisers, including 'Princess Teas' for the little 'uns with pop and less froofroo food). Fisherman's wharf is a good stop for fish & chips, pretty views, and seals (NB: that while feeding them is encouraged by some irresponsible locals, it's strictly forbidden and after the Steveston Sea Lion incident this year folks are starting to get the message not to interact directly with large sea mammals!)
Evening tour slots should also be available independently as well as through cruiselines, but HOHO I think stops running too early to be worthwhile for an evening stop.
Princess: Emerald, Golden x3, Island, Star x2
NCL: Gem, Pearl
Edumacational kiddie cruises: SS Uganda