From the GCL Twins Fan Site:

What is extended spring training?

Extended spring training, also called spring instructional league, is a series of games played under spring training rules to help younger players develop. Game are not reported, and there are no standings. Games are only played for bragging rights between the clubs involved and to evaluate the players. Extended Spring Training is also used to rehab players who have been injured and who are not ready to join their assigned teams.

Can anyone attend?

The games are open to the public. They are however, not reported, so scores are generally not posted here except when I've made it to a game. Please note that parking, concessions, etc., are similar to the Gulf Coast League as the games are played at GCL facilities and may be limited or non-existant. Don't forget to bring sunscreen because even if the weather is cool out, you can still get sunburn.

Who are the teams involved?

Each area of the country has different teams that participate.

In Southwest Florida, the teams involved are the Boston Red Sox, who play out of the Red Sox Developmental Complex on Edison Avenue in Fort Myers, FL; the Cincinnati Reds who play out of the Ed Smith Complex in Sarasota, Florida; the Baltimore Orioles who play out of Twin Lakes, Sarasota, FL; and the Pittsburgh Pirates with games located at Pirate City in Bradenton, Florida.

Are there player ages and/or roster limits?

None at all.

Can I listen to the games over the internet?

No. There is no broadcast of the games available.

Where are the Minnesota games played?

The Minnesota games are played at the Lee County Sportsplex on the Twins training fields in Fort Myers, Florida. Parking is generally free except for special events. To get to the complex, Exit 131 off I-75, west on Daniels Parkway to left on Six Mile Cypress Parkway. You will see the stadium on the right hand side. The practice facility is the building to the west of the main stadium, closest to Plantation Blvd. (You will see South Fort Myers High School just beyond it.)

I was there and there were signs that say "Keep Out!" or "Do Not Enter!"

Ignore them. Everyone else does. The signs are to keep people from parking in between the fields.

I tried to go to a game but they weren't playing or played earlier then listed?

All games are subject to change without notice and sometimes for rather questionable reasons. The league is very informal. If the visiting team doesn't show up, Minnesota may play an inter-squad game instead.

Where can I get a roster/schedule?

Rosters & composite schedules are available in the office, south of the workout building and batting cages. I will have updated rosters available online as the season progresses.

What is "Czech Nat."?

The Czech Republic National team is in camp to play Minnesota for several games. The Twins are one of the first teams in baseball to look at the Czech Republic as a potential provider of players to major league baseball.

When does it start?

Extended spring training begins April 12th and ends June 9th. The Amateur Draft will be held June 6th and 7th. Mini-Camp will be held June 11th through June 17th, with the Gulf Coast League beginning play on June 20th