As other agents have mentioned, there's no easy way to determine what a property may have sold for at that location. But it's not impossible to get an idea.
I used the house price index calculator on the federal government's web site, linked below. Using that, I found that a property purchased in the Chicago MSA in the third quarter of 1994 for $100,000 house would have sold for roughly $163,000 the third quarter of this year.
The MLS archives also shows three parcels of vacant land not far from the intersection you're asking about that sold in 1994. These three parcels were each a little over 1.5 acres and were forest preserve adjacent on 29th St. The lowest sale price was $34,900 and the highest was $42,000.
In the past twelve months, there have been three parcels of vacant land sell in Beach Park. There were two parcels, 1.5 acre parcel that sold for $91,000 and a 2.8 acre parcel that sold for $75,000. One parcel, 3/4 of an acre, sold for $24,000.
But there's a lot to consider. Subtle things like zoning can make a big difference. If you are looking to sell this parcel, you should contact a broker in that area and have them do a proper market analysis for you. If you need this information for insurance or other reasons, you may wish to contact an appraiser.
If you need a referral for either a broker or appraiser in that area, drop me a line.