The current background is an image of a square in Corinth that was paved by the believer Erastus. In the background you can see the Acrocorinth a steep 3 mile hike away.
When Paul was in Corinth the temple of Aphrodite sat atop the Acrocorinth. In the 5th century materials from the temple were used to build a church. In the subsequent centuries a series of castles were built atop the Acrocorinth to defend the city from invaders.
Erastus is mentioned in Acts 19:22, Romans 16:22, and 2 Timothy 4:20. He was the city manager of Corinth and became a minister with Paul. In 1928/1929 and 1947 an inscription was uncovered in the square as the city was being excavated confirming the Biblical account of Erastus – see the second picture below for the Erastus Stone that was uncovered.
The Erastus Stone
The Temple of Apollo in Corinth.
The image below is from the Acrocorinth above the city and shows Cenchreae and Lechaion, the 2 ports on either side of the Corinthian isthmus. When Paul visited the Acrocorinth it was the location of the temple of Aphrodite. The temple has been destroyed and ruins of a castle remains. 
The modern canal connecting Cenchreae and Lechaion, the 2 Corinthian ports. In Biblical times boats would be unloaded and carried overland the 4 miles. The canal is as straight as an arrow and was finished in 1893.