I also like Forks of the Credit. Rattlesnake Point is a good hiking place as well.
If you’re a hockey fan there’s the Hockey Hall of Fame.
A 2.5 hour drive to the east is Gananoque, ON, where you can take a boat tour of the Thousand Islands. I liked that so much that I did it twice, once when on a business trip and then with my wife when we returned.
The movie Fly Away Home (1996), about saving some Canadian geese, was filmed in the beautiful farmlands just to the northeast of Toronto. That’s in and near Lindsay, Kawartha Lakes, and the surrounding area. It’s pretty country.
For a romantic overnight getaway with loads of hotels, there’s Niagara Falls. You should be able to book something on short notice. It would be easily combinable with the Niagara on the Lake winery option mentioned by several upthread, which I definitely second.
The Canadian side of the falls has a better view and more developed tourist town than the American side. I’ve heard that some of the casinos cater to Chinese clients.
Did Dundas Peak Trail today. It was fine, easy, and hit the spot. Traffic back to Toronto took a while.
My friend has lived in Toronto about 10 years. Every one of her visitors wants her to guide to Niagra Falls, so I’m not making her go through that.
Markham has incredible Chinese food from every region. Kinda like combining the best of China with Canada. Different vibe to me from Vancouver’s Richmond district, which is more like little Hong Kong.
I did find out she likes anything made with flour and loves bagels, so tomorrow afternoon I may go on a bagel hunt. The idea of a traditional Jewish bakery intrigues me since I’m from the West Coast of America and don’t think I’ve ever been in a “real” one. That said, has anyone tried Bagel Time, which claims to bring Montreal style bagels to Toronto?
And it looks likely that I may be spending a lot more time in Toronto. So, saving all of these recommendations if I don’t get to them this time.
Haven’t tried Bagel Time. Kettleman’s is a relatively new addition to Toronto. Montreal bagels, but they are from Ottawa.
If you want the Toronto Bagel experience, go for Bagel World. If they have blueberry buns, get one. They are a classic Jewish Toronto speciality with a brioche dough and are especially good at this time of year.
The Thornhill location is only 10km away. Heck, I could even walk there and back to justify wolfing down a selection. 
If you’re thinking of bagels, there’s a St.Urbain https://sturbainbagel.com store in the St Lawrence Market, just east of the downtown core - http://www.stlawrencemarket.com . Built in the mid 1800’s, it now houses an art gallery on the second floor, the main floor and ground floor have about a hundred small food / grocery stores. The St Urbain bagel shop is in the south-east corner of the second floor.
Find Geddy Lee and get an autograph.
Unionville is very nice. If you saw the movie “PCU,” you’d recognize it as the place where the character Gutter gets picked up by George Clinton’s bus. If the TV show “Schitt’s Creek” is more to your liking, then you’ll recognize the Blouse Barn.
At any rate, I’d recommend Jake’s on Main as a pub/restaurant in Unionville. Probably the best patio in all of York Region; and probably also the biggest. I’d link, but their so-called “website” seems to have been hijacked by some “take a survey and win an iPhone” operation. But you cannot miss Jake’s. It’s at the north end of Main Street, almost opposite the Unionville Arms.
Just 15 or 20 minutes up the road is Stouffville (pronounced “STOW-villle”), where I lived for a number of years. The local pub was the Earl of Whitchurch. Good pub grub and a nice selection of taps. It’s been open and closed for the last number of years, but it’s always been a place for good food and cold beer. Stouffville itself is rather nice—see if there are any festivals in Clocktower Square, or enjoy the trails in the conservation area just north of town.
I’ve been through that lock a few times. It’s actually kinda scary in the upper bucket if your job is to be up on the bow to tie the boat up – especially if you don’t like heights – because if you fell out of the bucket it’s a long way down to the rocks below!
Today I walked 10 very interesting kilometers from Markham to Bagel World in Thornhill this afternoon. Of course, I didn’t pay attention to what time a bagel shop would close (hint: early afternoon) and got there about 30 minutes after it closed.
I love walking in a new city. You notice all sorts of stuff. I went from the new Chinese part of Markham, though much older neighborhoods. Changed from almost all Chinese/Asian to what seemed like all white folks out and about in the older section. All of the areas have reasonably new, well maintained, washed cars. The older section had nice older tree canopy as it was pretty hot in the sun, primarily one car garages, but all nicely maintained. There are all sorts of “hidden” pathways and shortcuts that Google Maps helpfully pointed out that I might have walked by.
I stopped for a pint of 100th Meridian beer at the Thornhill Pub, established 1883. It was a welcome chance to cool off and whet my thirst. I may have said a bad word or three when I actually got to Bagel World. Went to the nearby Promenade (?) mall for a double shot iced Americano whilst waiting for my friend to come by. Ate at a nice Thai restaurant in Markham with really good papaya salad, although the rest of the dishes were just okay.
Maybe breakfast at Bagel World and then to Mono Cliffs tomorrow? Not sure.
BTW, appreciate all the replies and taking notes since it looks like I may be spending a lot more time here moving forward. 
Bit of a hijack, but I grew up in Peterborough. There used to be a mini golf place just across the street from the canal at the bottom of the lift locks. I was there with a couple of friends one summer day playing mini-golf when we heard a loud bang, followed by an almighty splash. We ran across the street to check it out. A mid sized power boat had been in the up-going caisson which had risen about 10 feet when the gate latch failed and the gate opened. That was the clang we heard, the splash was all of the water, the boat, and it’s crew, pouring out of the caisson into the canal below. By the time we’d gotten there, the two people had made it to shore, but their boat was floating upside down in the canal. I didn’t hear anything more about it, if the boat owner had insurance to cover the damage, or if they tried to sue Parks Canada. I never heard of another incident like it.
Weekend traffic is bad on the way to Muskoka. Though easier during the week, it might be too far away. Worth returning in the autumn to see the trees get artsy. Montréal is a loveable city but is a hard slog from Toronto; distances in Canada are significant. The train is a good option but will cost you a full day, with driving not much faster. Best time to go is for the jazz and comedy festivals, if the wildfire smoke has settled down.
Niagara is worth a visit for wine or water but is pretty touristy.
Mono is on the Bruce Trail. It’s a pleasant place for an easy hike and there is a pleasant pub there. By Canadian standards there is nothing really special about it. If you like easy hikes through the woods or walking dogs it might be a good choice, but maybe it’s a long drive for what it is?
Fort York and seeing The Group of Seven are good options. It might be worth checking concert and sports listings, or seeing what is at the Royal Ontario Museum. I’ve never actually done the CN Tower thing. The Islands are not bad. Maybe Canada’s Wonderland is your thing. Find a buffet that serves Peking Duck? Visit Pacific Mall to load up on cheap electronics and assorted gewgaws?
I spent a little time on the road earlier and the weekend getaway traffic was heavy by 2 PM. 401 eastbound between Scarborough and Ajax is very crowded. The radio said that the roads north to Muskoka were bad too.
Meanwhile if you like wineries but don’t want to visit the Niagara area, there are some nice ones to the east. And in that area, if your friend likes baked goods, the bakery at the Big Apple in Colborne is great, with apple pies, strudels, apple dumplings and more. https://thebigapple.ca/
Just try to ignore the creepy anthropomorphic cartoon face painted on the side of the Big Apple itself.
I can confirm the wineries in Prince Edward County (turn right at Belleville); also, lavender farms!
Again, thanks for all the replies and suggestions! I’ll be revisiting my lady friend, and by extension Markham and Toronto in the near future. And looks to be frequently as well.
Whilst Bagel World turned out to be a bit disappointing as they offer pretty average bagels. It was definitely worth hoofing over 10 km through quaint older neighborhoods and footpaths to get there. Next time I will brave the traffic and get into the traditional jewish bakeries and see if that’s what I’m looking for. Trouble is, I am not quick sure what I’m looking for but more than confident I will recognize it when I find it.
Far more importantly, my lady friend and I are signed up to spend a lot more time together, which was the whole point of visiting Markham in the first place. 
Congrats on a successful vacation!
Toronto is not the best place to enjoy Montreal style baked goods. Some “Metro” grocery stores sell frozen St. Viateur bagels which may or may not be the second best available option. A trip to Montreal at some point is the best choice.
Glad you enjoyed Toronto!
Bolding mine…
Muskoka — what is this Muskoka? Slithers off to search… hey it looks pretty nice! Next time I’m in Toronto I may check it out. Cool. Thanks. (Images; it looks quite nice ➜ https://is.gd/95vQ45)
Montréal — yes it is quite a slog to there. Once, on a business trip to Montréal and wanting to visit all the MLB ballparks, I did that drive. It is long, and boring. Mind numbing. (Except that along the way I passed Gananoque and the Thousands Islands, posted upthread and well worth it). I drove to Toronto to catch a Blue Jays game and meet up with another Doper but unfortunately the timing didn’t work out; and he may have some ideas here (hello, DM?): @Le_Ministre_de_l_au-dela
Niagara — I’ve done that drive too, Niagara to Toronto and it’s not too bad and not too far. Although when I did it, it was in an ice storm and that was pretty sketchy going. In Niagara besides of course the falls and Nikola Tesla’s contributions there is the NFCC, Niagara Falls Curling Club, and that was a very fun day. I took the family there and we tried curling for the first time ever. The guy there gave us a brief lesson on the basics and then we had at it. Fun, enjoyable, and definitely memorable! The kids still talk about that one, several years later (they’re in their 30s now ).
Fort York, Group of Seven, Algonquin School — hmmm, a new one one me and this looks quite interesting; I’ll note it for next time, thanks. ➜ https://is.gd/40GX95
Royal Ontario Museum — I was wondering when someone was going to mention the ROM. It is an extensive collection, and quite large. I especially liked the exhibit on precious stones. I took the family there, on the same trip when we did Niagara and NFCC. We spent several hours at the ROM.
CN Tower — I’ve done this 2x. First time was with the family (on the Niagara / NFCC / ROM / ice storm trip), and then another time when I was on a business trip and I brought my wife.
Canada’s Wonderland — it’s an amusement park, oh, okay, thanks for the info ➜ https://www.canadaswonderland.com
Peking Duck — I have tried this, but not in Toronto. Yes it is tasty.
So, in the end I’ve been there 3x. 2x were on business trips and I got away a little bit to do some touring. The other time was on vacation (Niagara). If they’ll be helpful, on imgur I posted a handful of photos from our last visit to Toronto: Toronto / CN Tower; 1,000 Islands; Fly Away Home (1996) farmlands
