Doors open in Toronto this weekend as we all get a chance to peek inside buildings and spaces rarely open to the public. This is one of my favourite city-run events of the year and for past Doors Opens we've covered locales like the South Central Letter Processing Plant, The Design Exchange, Redpath Sugar, the TTC's Harvey Shops and BAPS Shri Swaminarayan Mandir.

This year, it's Doors Open's 10th anniversary and to mark the occasion the City of Toronto has found a number of new buildings to add to the agenda. If the city-wide event is anything like previous years it's best to head out as early as possible to avoid long line-ups. There's so much to see so realistically I usually narrow my focus to about 10 places - 5 on each day - and don't wait in lines any longer than 20-30 minutes. Too much time trying to get into one venue essentially kills even the best laid plans so I find it best to cut my losses and head directly to the next destination on my list.

There's also a bit of strategy involved in choosing buildings I think I'll never get a chance to get into again. Some of these places do Doors Open annually; or are open during Nuit Blanche or at some other point during the year. I tend to avoid these unless the lineups are short and/or they're in close proximity to other places I have on my list.

So, with that said, here are my top picks for what to check out at Doors Open Toronto 2009:

The Don Jail
This is the last chance to see The Don Jail before renovations begin and it transforms to its new life as part of Bridgepoint Health's new hospital. 1/2 hour guided tours are being offered of the cell blocks and the great Rotunda.

Regent Park Revitalization - First New Building
It's no secret the Regent Park is undergoing a major facelift and each time I pass by the new towers on my commute along Dundas East I wonder what the high-rises look like inside. Now I finally get a chance to find out as the first new building at 246 Sackville St. will be open for tours of the lobby and amenity areas. Note: This tour is only open on Sunday.

Stantec - Former McGregor Socks Factory
This imposing building at the corner of Wellington and Spadina housed the famous McGregor Socks Factory forever. How it's home to Stantec - a company few have probably heard of. But that doesn't matter. The point of going here is to see what they've done to the space - a heritage post and beam building that's now LEED certified. Note: This tour is only open on Saturday.

TTC - Greenwood Maintenance Shop
I love getting inside forbidden TTC areas during Doors Open. This stop promises a behind the scenes tour of machinery and equipment used to overhaul and repair big subway cars. TTC nerds rejoice! Note: This tour is only open on Saturday. Related: TTC Eglinton Garage Division.

BAPS Shri Swaminarayan Mandir
I couldn't not include this on my list. It's truly a spectacular building and as we've noted past years is well organized even if it seems to draw half the city. Previous coverage.

The CBC Building
A great venue for media buffs (or even just HNIC fans). The CBC goes all out for Doors Open and lets visitors meet some actors and staff they may or may not recognize. There will also be a weather centre demonstration from CBC News at Six weather expert Nick Czernkovich. For the good stuff, it's best to get here between 11 and 2. Note: This tour is only open on Saturday.

Artscape Wychwood Barns
Since the barns just opened last year, this is the first time they've made a Doors Open appearance. But I suspect they'll be back for years to come. Impressive space and worth stopping by if in the area, perhaps especially for a tour of the Stop's Green Barns.

Fire Hall 423 - The Junction
I'm sure I saw a Fire Hall as part of some school field trip when I was in grade 6, but that experience is but a distant memory. I don't expect anything earth shattering here - but still - Fire Hall! I'll stop in if I find myself anywhere near The Junction. Related: Fire Hall 425 - Swansea.

Shamrock Bowl
For those looking to spend a Friday night 5 pin bowling in the 1950's, this was the place to go. On Coxwell near Gerrard, this bowling mecca has recently undergone renovations and will not be open to the public until later this year. This is what I'd call a good place for a bit of a break as apparently visitors will be able to knock down a few pins.

Canada's National Ballet School
This is one of my favourite buildings in the city and I'm always up for repeat visits when given the chance. Note: Hours here are more restricted than other venues. Open from only 10am-1pm each day.

Coach House Press
This tiny and treasured book publisher in the Annex is always a Doors Open favourite. The guys that work here do such a great job showing off both the old and new equipment and answering questions about printing and binding.

For a complete list of venues, visit the official Doors Open Toronto web site.

Also, new this year, Scrolling.TO has created a web site they're calling the DoorsOpenScroller which works on both iPhones as well as Blackberrys and other mobile phones. It's not an app but instead a web site specifically formatted for mobile devices that includes the following features:

1. The complete Doors Open 2009 building guide, with details on venue highlights; opening hours and last admittance; address; phone number; parking; transit; and venue history.

2. Venue locations instantly mapped on Google Maps

3. One-click access to call venues from your mobile phone, BlackBerry or iPhone.

Find out more at Scrolling.TO.