Welcome to Walnut Grove Cemetery. This is a rather old cemetery in Prosper, Texas. The oldest date of death on any marker is from 1861, and the earliest date of birth is from 1801.
Walnut Grove Church was originally organized as Union Congregation in 1846, and became known as Walnut Grove Church in 1858. The first church building on the property was built in 1869. The church no longer exists on this property, but the cemetery remains.
To get the final coordinates for this cache, please answer the following question:
On the "Walnut Grove Presbyterian Church" historical marker near the pavilion, what is the year written under the plaque?

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Congratulations to Leprechaun49, PapawTexas, and QuadWrays for the First to Find