Possible Clues:

• Up with, with "of"
• Argosies originally entering a French port side by side
• Level area in a French port
• Sailor has to be at ease when first of admirals comes in alongside
• Be a star performing side by side
• Way to walk while conversing
• Side by side — in the picture
• A tough task keeping top of road level
• A brute crossing river keeping pace
• An early meal, dropping middle section to the side